Card drive apparatus and card

ABSTRACT

A head assembly moving along a long side of a magnetic card, more than one magnetic head rotating in the head assembly for reading/writing data, a rotary transformer and a carriage with a card holding mechanism for keeping a card at a predefined position are provided in a card reader of the present invention. A rotating part of the rotary transformer in the head assembly receives and sends a signal to the magnetic head and a fixing part of the rotary transformer is connected to a reading/writing circuit. On the card of the present invention, which is usually rectangular, there are tracks defined by plural arcs. The arcs are on plural same-size circles whose centers are aligned on one line along the long side of the card. A magnetic card or an optical card can be used for the present invention.

This application is a continuation of application Ser. No. 08/642,256,filed May 2, 1996, now abandoned which in turn is a division ofapplication Ser. No. 08/383,714, filed Feb. 2, 1995, now abandoned.

FIELD OF THE INVENTION

This invention relates to a data storage medium and to data read andwrite apparatus for use in a computer, and more particularly, thisinvention relates to magnetic and optical cards and card readers.

DESCRIPTION OF THE RELATED ART

The external storage that has come to be widely used is divided intothree major categories: the integrated circuit (IC) memory such as ROMor RAM which is being extensively applied in the field ofsemiconductors, the magnetic disk drives and magnetic tape drives usingthe techniques of magnetic recording such as hard disks or floppy disks,and optical recording techniques that include compact disks (CDS),write-once optical disks, and re-writable optical disk drives andmagneto-optic disk drives. All these apparatus feature large storagecapacity and random access capability except the magnetic tape drive.

Magnetic card readers and optical card readers are the major cardreaders in use. Rectangular cards, which are about the size of abusiness card, have several longitudinally arranged recording tracks.Unlike the magnetic disk drive with which data can be repeatedly readbecause of the circular recording tracks, the conventional card readeris disadvantageous in that data on a given track cannot be accessedrepeatedly due to its linear tracks, e.g., each single track is cut offat both ends.

FIGS. 120A to 120C give general description of a conventional magneticcard. FIGS. 120A and 120B are a sectional view and a top view,respectively, of a magnetic card whose surface is covered with magneticmaterial entirely, and FIG. 120C shows another type of a magnetic cardwhich is coated with magnetic material only partially. Underneath board1001 are magnetic film 1002, protective layer 1003, and printing layer1004. Board 1001 is made of PVC, PET, and synthetic paper and coatedwith thin magnetic film 1002 of a few micrometer thickness. Protectivelayer 1003 protects the magnetic film. On printing layer 1004, lettersare printed. On the board are another printing layer 1005 on whichpictographs are to be printed and a protective layer 1006. Magnetic cardillustrated in FIG. 120C is commonly used for cash cards, telephonecards, and credit cards, to name a few.

FIG. 121 illustrates the basic theory of a data read and data write fora magnetic card reader carried in an article of an in-house handbook forusing cards issued by one leading company in Japan. In this Figure, feedrollers 1007 and 1008 allow magnetic card 1000 to travel back and forth.Driving motor 1009 spins feed roller 1007 by means of belt 1010. Whenthe driving motor rotates in the direction of arrow A, magnetic card1000 placed between feed roller 1007 and pressure roller 1011 travels inthe direction of arrow B to the position between magnetic head 1012 andhead pressure roller 1013. While magnetic card 1000 passes throughmagnetic head 1012, data is written onto or read from the magnetic layer1002 on the magnetic card, which is then sent to feed roller 1008 andpressure roller 1014. Feed roller 1007 and feed roller 1008, both ofwhich are identical in diameter, are linked by means of belt 1015. Thus,the magnetic card travels from feed roller 1007 to feed roller 1008 at aconstant speed in the direction of arrow B, and then is ejected.

After data recording or reproducing, it is also possible to reverse themotor rotation so as to reverse the magnetic card to be ejected from theinsertion slot. Conventionally, two or more magnetic heads read or writedata while a magnetic card is traveling in one direction. Therefore thecard could store only scores of bytes. Moreover, a user had to insert amagnetic card again into a slot of a magnetic card reader whenever theuser wanted to re-access the same information.

Several attempts have been made to solve the above-mentioned problems byusing a rotation drum found in a video tape recorder or a tape drive forstoring data. They embrace a method of reading or writing data withseveral magnetic heads on a rotation drum by helically scanning amagnetic tape wound on the drum. The magnetic heads are mounted on thecircumference of a turntable to form arc tracks on a magnetic storagemedium. It is important to note that these methods aim at obtainingnon-linear recording tracks, and signals are transmitted to and from themagnetic head by means of a rotary transformer.

"THE MAGNETIC CARD READER" introduced in Japan Patent Application Sho62-194717 sets forth the structure that forms tracks with two or moremagnetic heads on the turntable. The rotation of a turntable and themovement of a carriage on which the turntable and a motor are mounted,are linked by the single motor. It is an improvement that the loci oftracks on a storage medium are not circular but continuous spirals.

"MAGNETIC CARD AND MAGNETIC CARD ISSUER" of Japan Patent Application Sho63-228212 calls for a method of storing data on a circular track shownin FIG. 122 instead of the striped tracks in FIG. 120C. Data is recordedon a circular track 1017 with magnetic head 1016 on the recordingsurface of a magnetic card. When a circular track is used and magnetizedat a density with 210BPI/75BPI specified by the Japanese IndustrialStandard, the track length becomes 1.7 times longer than theconventional striped tracks if the diameter of the circular track is 38mm. This method is unique in that it employs only one circular track ona magnetic card.

FIG. 123 illustrates a method presented in "DATA CARD READER" of JapanPatent Application Sho 59-66777. The tracks of this invention arearc-shaped and aligned in the longitudinal direction of a magnetic cardwhich is the size of an ID card (JISB-9560). On magnetic card 1000having an effective length of about 80 mm, up to 3,000 arc tracks T-1,T-2, etc. measuring 55 mm in width and 26 micrometers in track width canbe stored. The characteristic of this method is that magnetic heads arelifted from a magnetic card on rear tracks (left edge of the card inFIG. 123).

Japan Patent Application Sho 62-223468 and Japan patent Application Hei1-218020 also introduced the method of using uni-directional arc tracksas shown in FIG. 123.

FIG.124 illustrates a method introduced in "THE METHOD OF POSITIONINGMAGNETIC CARD FOR MAGNETIC STORAGE DRIVE" of Japan Patent ApplicationHei 2-24759. The starting track number and the ending track number ofarc tracks 1018 are recorded on the header (not shown). By comparingthese track numbers, the extent of track deviation is detected. Afterinserting locking pin 1019 to a hole on one side of the magnetic card, acard is positioned by moving adjustable pins 1020, which are insertedinto two holes located on opposite sides with locking pin 1019 as thecenter. Rotation motor 1022 that rotates magnetic head 1021 is locatedoutside of the magnetic card and the magnetic head 1021 is placedoutside of the magnetic card when it is not operating.

"MAGNETIC RECORDING CARTRIDGE" of Japan Patent Application Hei 2-157358describes a magnetic recording cartridge. A carrier mechanism that movesa magnetic card forward, magnetic heads and several supporting arms forthe magnetic heads are housed in a single storage case. A largerectangular hole is made in the center of two groups of arc tracks sothat a magnetic card will be transported without being hindered by anycomponents such as a rotation shaft.

The arc recording tracks make it possible not only to increase thenumber of tracks but also to re-access a certain track continuously whencompared to conventional the striped magnetic card.

PROBLEMS TO BE SOLVED BY THE PRESENT INVENTION

Magnetic card readers have been typically incorporated into a device ofsubstantial size that could be installed on the floor or on the desk.This fact has rarely brought the downsizing of the card reader into thefocus of attention. The adoption of arc tracks could improve the storagecapacity by two-digits or more compared to the conventional magneticcards. This improvement will further promote use of magnetic cards as anexternal storage device of a computer. The magnetic card can supersede afloppy disk in the future. The sub-notebook type of personal computernow on the market is assumed to be the limit that can mount a 3.5"floppy disk physically. The main reason that hampers the floppy diskfrom being downsized from its current 3.5" inches is the size of afloppy disk cartridge. IC memory that physically fits the standardizedPCMCIA dimensions or super-small hard disks are projected to become themainstream of tomorrow. The 3.5" floppy disks can no longer keep abreastwith the technological advancement in which small-portable devices aremoving to the center stage. Thus, the objectives of this invention areto secure as large a card size as possible, to make the most of therecording surface on the card, and to ensure performance andenvironmental resistance that can parallel those of conventional floppydisks.

The problems to be tackled to achieve a small card reader thus breakdown into the following five;

1. An apparatus should have a highly reliable data read and writemechanism with high recording density. In order to expand the storagecapacity of a card, the card will be widened in a transverse directionas much as possible to increase the number of recording tracks.

2. The card must be shortened in longitudinal direction so as tominimize the traveling length of the card for data access. To ensurehigh recording density, the distance between the head and the card mustbe stable and small.

3. To protect the card from human fingerprints or dirt, the magneticfilm and protective layer indicated in FIG. 120A are provided. Becausethe card must be inserted into the card reader by the user, it isimportant to design a card that is problem-free from dirt orcontaminants that might be carried by the user.

4. A card reader should automatically or semiautomatically introduce acard into the card reader and into a designated position without hittingagainst any obstacle such as a head,

5. A card reader should achieve high random-access capability to a giventrack.

6. A card reader should overcome the problem of error-occurrence when acard has been inserted in the wrong direction. Conventionally, a cardinserted in the wrong direction was ejected from the device, requiringthe user to reinsert it into the device.

The magnetic head in the conventional techniques is rotated either incircles or in spirals. Of the former, the loci formed on a card can be acircle or an arc. Furthermore, the arc tracks can be aligned in onedirection or face each other in the longitudinal or transverse directionon the card. With respect to the relationship between the magnetic headand a magnetic card, the magnetic head can always exist on the surfaceof a magnetic card or it can exist on the card only during data read andwrite and otherwise can be placed out of the magnetic card. Also, thereare two types of magnetic cards: one is directly handled by the user andthe other is not. The magnetic cards that are in a hermetically sealedcontainer or under a specially clean environment are not touched by theuser.

To address the above-mentioned five challenges, the magnetic card of thepresent invention uses a flat card having no additional workings on thesurface except punching holes of small diameter just like the prepaidcard. The card of the present invention will be problem-free underconstant handling by the user. The card reader of the present inventionhas the following characteristics:

The magnetic head forms arc loci. Tracks on the magnetic card aredivided into two groups of arc tracks facing each other in thelongitudinal direction, and the magnetic head is always placed on themagnetic card. In addition, the storage capacity of arc tracks facingeach other by far surpasses that of arc tracks aligned in one direction.Moreover, with the magnetic head existing on a magnetic card all thetimes, the space between the magnetic head and the card can be minimizedand controlled accurately, thus rendering the apparatus easy to operatejust like the floppy disk unit.

By contrast, for a magnetic head moved in from outside to makeinstantaneous contact with a magnetic card, the surface height of themagnetic head must match that of the magnetic card, which adds onlycomplexity to the pressure mechanism of the magnetic head or the padstructure that supports the magnetic card.

The present invention is directed to a technique which overcomes theabove-discussed disadvantages. Thus, the objectives of the invention areto achieve a large data storage capability on a card which can beaccessed randomly with the card being mounted on a card reader. Namely,the primary objectives of the present invention are to achieve a cardand a card reader that are capable of continuous data write, retrieval,and read of an ever-increasing amount of data, ensuring the excellentperformance that parallels magnetic disk drives and almost up to opticaldisk drives.

SUMMARY OF THE INVENTION

A card drive apparatus according to one aspect of the present inventionfor accessing a plurality of recording tracks on a card includes a headassembly, a carriage and a carriage positioning mechanism.

The head assembly has at least one access head for accessing tworecording tracks, wherein the two recording tracks are arc trackslocated at different places on one circumference on the card. The headassembly has a turntable for mounting the access head, and a shaft forrotating the turntable there around.

The carriage steadily holds the card therein and provides an accessopening for accessing the card therethrough.

The carriage positioning mechanism is for positioning the carriageagainst the head assembly through the access opening so that the accesshead accesses the two recording tracks on the card at one position.

The head assembly includes a motor for rotating the shaft.

The head assembly includes a rotary transformer and a transformer holderfor holding the rotary transformer.

The carriage includes a carriage base, a card feeding mechanism forfeeding the card to the carriage base, a card positioning mechanism forpositioning the card at a predefined position of the carriage base, anda card holding mechanism for keeping the card at the predefinedposition.

The carriage includes a card ejecting mechanism for ejecting the card,wherein the card ejecting mechanism includes means for releasing thecard from the card holding mechanism, means for feeding back the cardand means for detecting the ejection of the card.

The card drive apparatus according to another aspect of the presentinvention includes an apparatus base and the carriage positioningmechanism includes a mechanism for fixing the carriage to the apparatusbase, and a mechanism for moving the head assembly so that the accesshead mounted on the head assembly seeks the recording track on the cardthrough the access opening.

A card according to one aspect of the present invention is a magneticcard or an optical card or an magneto-optic card.

BRIEF DESCRIPTION OF THE DRAWINGS

By way of example, the embodiments of the invention will be describedwith reference to the accompanying diagrammatic drawings of which,

FIG. 1 depicts an example of a rotational mechanism of magnetic heads ofa magnetic card reader of the present invention;

FIG. 2 gives another example of a rotational mechanism of magnetic headsof a magnetic card reader;

FIGS. 3A-3D show other examples of rotational mechanisms of magneticheads of a magnetic card reader;

FIGS. 4A-4C depict examples of a magnetic head assembly for a magneticcard reader;

FIGS. 5A and 5B show examples of mounting magnetic heads on a turntableusing long arm springs;

FIGS. 6A-6C show examples of attaching stoppers and cleaners to aturntable or a rotary transformer holder of this invention;

FIGS. 7A-7C depict examples of mounting a rotary transformer on themagnetic card reader of the present invention;

FIGS. 8A-8C depict other examples of mounting a rotary transformer onthe magnetic card reader;

FIGS. 9A-9C show the circuitry of a rotary transformer;

FIGS. 10A-10E are circuit diagrams that show the operation of a rotarytransformer;

FIGS. 11A and 11B illustrate examples of using a magnetic head and itsloci of the present invention;

FIGS. 12A-12C depict the recording tracks on a card for the card readerof the present invention;

FIG. 13 shows the recording tracks and the side margins on a card of thepresent invention;

FIG. 14 is a diagram that indicates the relations between the anglebetween the center line and the end of a track and Z;

FIGS. 15A-15C show examples of the azimuth recording method of thepresent invention;

FIGS. 16A-16C indicate the cross sections of an optical card structureof the present invention;

FIGS. 17A and 17B depict examples of a head assembly, in which data readand write is performed, of an optical card reader of the presentinvention;

FIGS. 18A and 18B depict cross sections of data read and write apparatusof an optical card reader of the present invention;

FIG. 19 is another example of data read and write apparatus of anoptical card reader of the present invention;

FIGS. 20A and 20B give another example of data read and write apparatusof a magnetooptic recording format of the present invention;

FIGS. 21A and 21B illustrate magnetic fields at the head in the opticaland magnetic recording format of the present invention;

FIGS. 22A-22C show some shapes of a recording medium for an optical cardof the present invention;

FIGS. 23A and 23B show some shapes of a recording medium for an opticalcard of the present invention;

FIGS. 24A and 24B show embodiments of a card reader of the presentinvention;

FIGS. 25A-25E show one embodiment of a card detect mechanism of thepresent invention;

FIGS. 26A and 26B show one embodiment of the card detect mechanism usingan optical detector, of the present invention;

FIGS. 27A-27C show one embodiment of a feeding mechanism for feeding acard into the card reader of the present invention;

FIG. 28 shows another embodiment of the feeding mechanism of the presentinvention;

FIGS. 29A and 29B show other embodiments of the feeding mechanism of thepresent invention;

FIGS. 30A-30E show embodiments of a pressure pad mechanism applied onthe feeding mechanism of the present invention;

FIGS. 31A and 31B show embodiments of the pressure pad mechanism appliedon the feeding mechanism of the present invention;

FIGS. 32A and 32B show another embodiment of the pressure pad mechanismapplied on the feeding mechanism of the present invention;

FIGS. 33A-33C show another embodiment of the pressure pad mechanismapplied on the feeding mechanism of the present invention;

FIG. 34 shows one embodiment of a track seek mechanism of the cardreader of the present invention;

FIG. 35A shows an assembly structure of a pad frame and a pressure padof the card reader of the present invention;

FIG. 35B shows a positioning mark printed on the card of the presentinvention;

FIG. 35C shows signals detected by an optical sensor of the presentinvention;

FIG. 36 shows one embodiment of the feeding mechanism of the card to acarriage base of the present invention;

FIG. 37A shows a card holder of the present invention;

FIG. 37B shows a card of the present invention;

FIG. 37C shows the card in the card holder of the present invention;

FIG. 37D shows a section of the card holder of the present invention;

FIGS. 38A and 38B show one embodiment of the sector format;

FIG. 38C shows a rotor and an optical encoder;

FIG. 39 shows a relation between a sector pulse and an index pulse;

FIG. 40 shows one embodiment of the card reader of the presentinvention;

FIG. 41 shows a block diagram of circuits in the card reader of thepresent invention;

FIG. 42 shows a sideways moving mechanism of a card holding mechanism ofthe present invention;

FIG. 43A shows th e relationship between the coil-type magnetic head andthe reading track;

FIG. 43B shows the MR head and the recording track;

FIG. 43C is an experimental result showing the loss of the distance ofthe magnetic heads shown in FIGS. 43A and 43B;

FIG. 44 is a sectional view of the magnetic card of the invention;

FIGS. 45A-45D show a principle of the magnetic card with a protectivecover;

FIG. 46 shows a read/write circuit using a new method for electric powersupply;

FIGS. 47A-47C show examples of configurations using a plurality of theslip rings;

FIG. 48 shows a configuration of the read/write circuit of theinvention;

FIG. 49 is a plan view showing the magnetic head adjusting mechanismaccording to the invention;

FIG. 50 is a sectional view showing the magnetic head adjustingmechanism;

FIG. 51 is a sectional view showing the magnetic head adjustingmechanism in the pitching direction;

FIG. 52 is a sectional view showing the magnetic head adjustingmechanism in the rolling direction;

FIG. 53 shows interference stripes which appear when the contacting partof the slider of the magnetic head and the glass plate;

FIG. 54 is a plan view showing the magnetic head adjusting mechanism inmoving on the plane;

FIG. 55 is a sectional view showing the magnetic head adjustingmechanism in the rolling direction;

FIG. 56 is a plan view showing the magnetic head adjusting mechanism;

FIG. 57 is a sectional view showing the magnetic head adjustingmechanism in the rolling direction;

FIG. 58 is a plan view showing the magnetic head adjusting mechanism;

FIG. 59 is a plan view showing the magnetic head adjusting mechanism;

FIG. 60 is a sketch showing the magnetic head and a card holdingmechanism according to one embodiment;

FIG. 61 is a sketch showing the magnetic head and another card holdingmechanism according to another embodiment;

FIG. 62 shows another embodiment using two parallel flat springs;

FIGS. 63A and 63B show another embodiment using another supportingmechanism for the pressure pad of Embodiment 42;

FIG. 64 shows another embodiment using another supporting mechanism forthe pressure pad of Embodiments 42, 43;

FIG. 65 shows another embodiment using another supporting mechanism forthe pressure pad of Embodiment 39;

FIG. 66 illustrates the magnetic head having a spherical or projectedcontacting part;

FIGS. 67A-67D show inserting operation of the magnetic card according toone embodiment;

FIG. 68 shows a dust remover according to one embodiment;

FIGS. 69A and 69B show examples of notches of the dust removers;

FIG. 70 shows the dust remover provided with the turntable;

FIG. 71 explains the operation of the dust remover;

FIG. 72 shows another supporting mechanism of the dust remover accordingto one embodiment;

FIGS. 73A-73C show three different examples of placements of the dustremovers according to another embodiment;

FIG. 74 shows a perspective view of the portion of loading the magnetichead according to the present invention;

FIG. 75 shows a cross section taken on line A--A of FIG. 74;

FIG. 76A shows a cross section of a portion of loading the magnetic headaccording to another embodiment of the present invention;

FIG. 76B shows a view of the operation of embodiment of FIG. 76A;

FIG. 77A shows a cross section of a portion of loading the magnetic headaccording to another embodiment of the present invention;

FIG. 77B shows a view of the operation of embodiment of FIG. 77A;

FIGS. 78A-78C show views of a track format on the magnetic card;

FIG. 79 shows a view of the track format of the front and rear tracks onthe magnetic card;

FIGS. 80A-80D show flow-charts of a sequence until the magnetic headdetermines its position at the front track;

FIG. 81A shows an arrangement of the recording track on the magnetichead;

FIG. 81B shows an arrangement of the magnetic head on the turntable;

FIG. 82A shows an arrangement of the recording track on the magneticcard;

FIGS. 82B and 82C show arrangements of the magnetic head on theturntable;

FIG. 82D shows an explanatory view of a period for the magnetic headrecording;

FIG. 83 shows an arrangement of the recording track on the magnetic cardand the magnetic head on the turntable;

FIGS. 84A-84C show embodiments of the head cleaning card;

FIGS. 85A-85C show embodiments of the head cleaning card;

FIGS. 86A and 86B show views of feeding the head cleaning card;

FIG. 87 shows a perspective view of a card feeding mechanism of thepresent invention;

FIGS. 88A-88C show sections of a moving card feeding mechanism of thepresent invention;

FIGS. 89A-89C show sections of a moving card feeding mechanism ofanother embodiment of the present invention;

FIG. 90 shows a perspective view of the card feeding mechanism ofanother embodiment of the present invention;

FIG. 91 shows a recording track pattern of the present invention;

FIG. 92 shows a perspective view of the card feeding mechanism ofanother embodiment of the present invention;

FIG. 93A shows a sectional view at the line A--A of FIG. 92 and shows acondition that the card can be inserted and extracted;

FIG. 93B shows a sectional view at the line A--A of FIG. 92 and shows acondition that the card is applied on the carriage base;

FIG. 94 shows a perspective view of the carriage base shown in FIG. 92;

FIG. 95A shows a perspective view of the carriage base applied with acard lifter;

FIG. 95B shows how the card lifter is installed with the carriage base;

FIG. 95C shows a condition where a magnetic card is applied on the cardlifter;

FIG. 95D shows another condition of the card lifter being installed withthe carriage base;

FIG. 96 shows a perspective view of the carriage base applied withpositioning pins;

FIG. 97A shows a card wherein positioning holes are made;

FIG. 97B shows a card wherein positioning holes are made to be symmetricwith respect to a center point of the card shown in FIG. 97B;

FIG. 98A shows a condition where the card has been inserted into thecarriage base perfectly;

FIG. 98B shows a condition where positioning pins come just under thepositioning holes;

FIG. 99 shows a perspective view of the carriage base applied with thepositioning pins and the lifters;

FIG. 100A shows a condition where positioning pins are supported by flatsprings fixed to the back side of the carriage base;

FIG. 100B shows a slanting positioning pin;

FIG. 100C shows a condition where a guide part is installed on thecarriage base and the positioning pins are pressured upward by acompression spring;

FIG. 101 shows a card having positioning holes at the front of the card;

FIG. 102 shows a perspective view of the carriage base appliedpositioning pins corresponding to the card in FIG. 101;

FIG. 103 shows a card on which two holes are not aligned on the sameline parallel to a long side of the card;

FIG. 104A shows a carriage base wherein a flat spring supporting thepositioning pins can move upward by an arm;

FIG. 104B shows a side view wherein the flat spring supporting thepositioning pins goes down by contacting the arm;

FIG. 105 shows a perspective view of the card feeding mechanism whosecard holder goes up and down vertically against the carriage base;

FIG. 106A shows a side view wherein the card holder of the card feedingmechanism in FIG. 105 goes down;

FIG. 106B shows a side view wherein the card holder of the card feedingmechanism in FIG. 105 goes up;

FIG. 107 shows a side view wherein positioning pins of the card feedingmechanism in FIG. 105 come just under the positioning holes;

FIG. 108 shows an enlargement of a card bias spring, whose pressureagainst the card can be removed, in the card feeding mechanism in FIG.105;

FIG. 109A shows a section wherein the card holder goes up against thecarriage base in the card feeding mechanism applied with the card biasspring in FIG. 108;

FIG. 109B shows a section wherein the card contacts the card bias springin the card feeding mechanism applied with the card bias spring in FIG.108;

FIG. 109C shows a section wherein the card holder goes down against thecarriage base in the card feeding mechanism applied with the card biasspring in FIG. 108;

FIG. 110A shows a condition wherein the card holder goes down in thecard feeding mechanism wherein a link is used for making the card holdergo up and down;

FIG. 110B shows a condition wherein the card holder goes up in the cardfeeding mechanism wherein a link is used for making the card holder goup and down;

FIG. 111 shows a perspective view of the card reader of anotherembodiment of the present invention;

FIG. 112 shows how the card reader of the present invention isassembled;

FIG. 113 shows a side view of the card reader of the present invention;

FIG. 114 shows a track layout of the card of the present invention;

FIG. 115 shows a diagram for calculating a track layout of the card ofthe present invention;

FIG. 116 shows a diagram for calculating a track layout of the card ofthe present invention;

FIG. 117 shows a diagram for calculating a track layout of the card ofthe present invention;

FIG. 118 shows a diagram for calculating a track layout of the card ofthe present invention;

FIG. 119 shows a relation between a track pitch and a total tracklength;

FIGS. 120A-120C show structures of conventional magnetic card;

FIG. 121 shows a basis of a conventional magnetic card reader;

FIG. 122 shows a track layout of a conventional card;

FIG. 123 shows a track layout of a conventional card; and

FIG. 124 shows a track layout of a conventional card.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Embodiment 1

With reference now to FIG. 1, the structure of a magnetic card readerwill be discussed, first with focusing on the mounting mechanism of amagnetic head.

FIG. 1 depicts the rotation mechanism of magnetic heads 13a and 13b. Amagnetic head is composed of a magnetic material referred to as the coreand a coil is wound around it. The individual magnetic heads are setinto sliders which are attached symmetrically on the surface ofturntable 15 with rotating shaft 16 in their center. The details of aslider are explained later. With magnetic heads set on, turntable 15rotates at a certain speed in the direction of arrow C. If only onemagnetic head is attached, one more dummy head, or a magnetic head, isattached to attain a balanced rotation of the turntable. The turntablein FIG. 1 rotates with its magnetic heads 13a and 13b on. The edge 15hon its circumference makes contact with magnetic card 1a. Being attachedon gimbal spring 19, which is a plane spring normally works inperpendicular motion, magnetic heads can pop up a bit higher thanturntable 15. Thus the force is applied in the upward direction so as topush up magnetic card 1a.

The magnetic card reader according to the present invention can beapplied to both the normal horizontal magnetic recording method and theperpendicular magnetic recording method. In either case, the adhesionbetween a magnetic head and a recording medium is the most importantfeature of magnetic recording. Widening of a gap between a magnetic headand a recording medium thus invariably reduces efficiency, and if worse,disables data read and write. This is particularly true for theperpendicular magnetic recording method. Gimbal springs 19 are employedspecifically for the purpose of narrowing the gap between a magnetichead and a recording medium and are critical to a magnetic recorder.

Edge 15h of the turntable 15 protrudes from base 15g onto which magneticheads 13a and 13b are mounted in the direction of magnetic card 1a to acertain height. The edge 15h is to keep the distance fixed from themagnetic card 1a to the turntable base as well as to protect themagnetic heads. When carriage base 189 (FIGS. 27A to 27C) is provided tocarry a card, the edge 15h of the turntable 15 is set lower than a basesurface of the carriage base 189 because the base surface 189b of thecarriage base 189 keeps the fixed distance between magnetic card 1a andmagnetic heads 13a and 13b. Thus turntable 15 rotates without makingcontact with magnetic card 1a when the carriage base is provided. Inaddition, as shown in FIGS. 31A and 31B, pressure pad mechanism, whichworks as kind of a pad, counterpoised to the magnetic heads of amagnetic tape recorder, applies pressure evenly down on magnetic card1a. The upward pressure of the gimbal spring 19 and the downwardpressure of this pressure pad mechanism therefore counterbalance themagnetic card. The function of this pressure pad mechanism is explainedin details later on.

It is difficult to electrically connect the input/output wiring of theread and write coils of magnetic heads with read and write circuits.This is because, unlike a magnetic tape unit or magnetic disk unit,magnetic heads themselves also rotate according to the presentinvention. To handle this problem, a rotary transformer commonly usedfor a VTR is applied. From the read and write circuits, the recordingsignal flows to the coils of the magnetic heads via the rotarytransformer and the reproducing signal is transmitted from the magnetichead to the read and write circuits via the rotary transformer. Thetheory of the rotary transformer is explained later with reference toFIGS. 9A to 9C. The secondary coil of the rotary transformer iscontained inside turntable 15 and rotates together with it. The primarycoil of the rotary transformer, on the other hand, is housed insiderotary transformer holder 20, which is installed on apparatus base 21.

Direct Current (DC) motor 22 is a flat-type motor commonly used forfloppy disk units, and consists of stator 22a and a rotor 22b. Stator22a is made up of a coil and a yoke and rotor 22b is made up of a magnetand a body of rotation. Rotation shaft 16 spins rotor 22b of DC motor22, and the rotor, in turn, rotates the turntable.

Embodiment 2

FIG. 2 gives another example of the rotation mechanism of a magnetichead. In this embodiment, a cylinder itself does not rotate but onlysupports a magnetic card. Rather, the turntable inside the cylinderrotates to write data or read data from a card.

The turntable in Embodiment 2 is flat, namely edgeless, which is thesalient distinction from Embodiment 1. Instead, the turntable issurrounded by elongated frame edge 20h of rotary transformer holder 20installed on apparatus base 21. Thus, the rotary transformer holder doesnot rotate. The cross sections illustrated in FIGS. 5A and 5B give abetter understanding of this structure. Elongated frame edge 20h of therotary transformer holder can be heightened or shortened. It can be sethigh enough to make contact with a magnetic card or set lower so as notto contact the card.

With regard to carriage base 189 provided to carry a magnetic card, itsbase surface 189b can be set lower than the top position of magneticheads 13a and 13b or can be set slightly higher to make magnetic heads13a and 13b contact the cards depending upon purposes.

The purpose of setting the base surface 189b of the carriage base alittle higher than the head top position is mainly to protect themagnetic heads from being damaged or destroyed by the ends of a card ifthe carriage base runs out of control. By contrast, setting the basesurface 189b of the carriage base a bit lower than the head top positionhelps maintain a certain distance between a magnetic card 1a and thebase of the turntable 15, and removes dust brought in from outside alongwith the magnetic card and keeps the magnetic heads from beingcontaminated.

Unlike Embodiment 1, in which the magnetic surface of a magnetic card isin constant friction with the edge 15h of the rotating turntable 15,this embodiment takes effect particularly in using a thin magnetic filmor a medium of low abrasion resistance for the card, or when the DCmotor torque is insufficient.

Embodiment 3

Referring now to FIG. 3, the method of protecting magnetic heads and thestructure of the edge of a cylinder that works as a spacer are explainedbelow.

FIG. 3A is a diagram that shows the rotation mechanism of magnetic headsfor a magnetic card reader. Based on the structure of the turntabledescribed with FIG. 1, a card flier is provided to edge face 15m, thepart that makes contact with a magnetic card, of edge 15h of theturntable. The flier controls the flow of air generated near edge face15m and generates the force with which to fly a magnetic card (in thedirection of arrow E in FIG. 3B) from the edge face 15m of the rotatingturntable 15. This mechanism helps reduce the friction between amagnetic card 1a and the edge 15h of the turntable 15, and the load ofDC motor 22, therefore, greatly serves the purpose of prolonging thesliding life of recording media. As the peripheral speed of turntable 15accelerates, the flying force to the magnetic card 1a grows inaerodynamic proportion.

FIGS. 3B to 3D show the cross section of magnetic card 1a and edge 15hof the turntable 15. In FIG. 3B, where air is flowing in, the edge isslightly skewed 15a, and the part with which a magnetic card makescontact 15b is rounded a bit so as not to damage the card. Then the edgeis concaved 15c.

A serrated edge, having no flat bases, will also be very effectivebecause it is this skewness that moves a magnetic card forward, in thedirection of arrow E, through the air flow. The flying force isdetermined by the angle of inclination or the surface area of the skewedpart of the edge, and the number of rotations of the turntable or therotational speed of the turntable relative to a magnetic card. On theother hand, the flying distance is obtained by the balance between theweight of a magnetic card that is applied in the direction counter toarrow E and the force applied by the pressure mechanism. The edge faceof the turntable is uniformly concaved and projected so that the flyingforce will be evenly applied onto a magnetic card.

The model in FIG. 3B, however, is advantageous if the start-up time ofthe turntable is short and thus a magnetic card will be up in the air ina short time. But if the rotational speed is low and the start-up timeis long, the initial contacting time also becomes longer, bringing apossible damage to the magnetic card. Moreover, a card tends to remainmore or less touching the edge without completely flying throughout theoperation. FIG. 3C therefore presents an improved model that eliminatesthe above problem. The top of the edge is more flattened to prevent thesurface of a magnetic card from being damaged. The load friction isdetermined by balancing forces among the total area of flattened top 15bof edge 15h, the flying force, the dead weight of the magnetic card, andthe pressure mechanism.

FIG. 3D gives another example of making the whole structure of FIG. 3Bmore smooth to eliminate the adverse effect that might be inflicted upona card during contact.

Embodiment 4

Referring now to FIGS. 4A to 4C, three types of a magnetic heads areenlarged upon below.

For all three types,. magnetic heads are incorporated into sliders 23a,23b, and 23c except head gap 24 which is exposed to make contact with amagnetic card.

Flat slider 23a shown in FIG. 4A and button-shaped slider 23b shown inFIG. 4B are mainly used for floppy disk drives. FIG. 4C is flying typeslider 23c used for hard disk drives.

Flat-type slider 23a is a double-barrel type slider which issymmetrically divided into two contacting parts 25a and 25b to stayevenly balanced on a magnetic card. The surface areas of the slider aresmall to reduce the sliding friction. Head gap 24 is located outside therotation shaft, in back of the center of one of contacting parts 25b ofthe slider to distance itself from the air inlet. Therefore, even whenfront edge 23t of the slider begins to fly a bit, the distance betweenthe recording surface of a magnetic card and the head gap is minimized.Either square gimbal spring 19a or oval gimbal spring 19b of FIG. 4Bwill be used. Gimbal spring 19a is designed to make the two contactingparts 25a and 25b of the slider contact the recording surface of amagnetic card with equal spring pressure. The gimbal spring ismulti-dimensional in its movement. This versatility allows the magneticheads to follow the movement of a magnetic card accurately. However, itis disadvantageous in that the tolerance for vertical movement is small.The contacting parts 25a and 25b are set slightly higher than edge 15hof the turntable in FIG. 1 and edge 20h of the rotary transformer holderin FIG. 2 in order to lift up a magnetic card. At the same time, apressure pad pushes down on the magnetic card to absorb vibration ordeviation which could be generated as magnetic heads rotate at a highspeed. The function of a pressure pad is explained later.

The button-type slider shown in FIG. 4B has a rounded surface on top ofwhich the head gap is positioned. This structure helps decrease the areathat contacts with the recording surface of a magnetic card. Unlike thedouble-barrel type contacting parts 25a and 25b in FIG. 4A, which keepfollowing the recording surface rather smoothly, a substantial amount ofpressure is applied against the recording surface as this button-typeslider 23b makes contact with it. Gimbal spring 19b of this example ismore powerful in its elasticity than the previous one.

The model in FIG. 4C shows a flying type slider used for hard diskdives. Flying type slider 23c shares some of the structuralcharacteristics with flat-type slider 23a in that they both have twocontacting parts (26a and 26b in FIG. 4C) and in their head gappositioning (24 in FIG. 4C).

However, flying type slider 23c is attached onto the tip of thin longarm spring 30 with a flexure (not shown) made of composite metal steel,which permits the flying type slider to move in the directions of X andY. The main feature of the long arm spring is its capability of movingin vertical direction Z freely. Thus its vertical motion can be set at adesired level.

A slider, a spring with a projection (32a, 32b, 32c, and 32d in FIGS. 5Aand 5B), and magnetic heads 13a and 13b constitute a part of a magnetichead assembly that slides through the recording medium of a magneticcard.

It is also possible to rotate the magnetic heads at such a high speedthat the magnetic heads keep flying on a magnetic card, using aflat-type or flying-type slider. For the double-barrel contacting parts,the design of a magnetic head slider for hard disk units will be readilyadopted.

Embodiment 5

Embodiment 5 will focus on the structure of the head support mechanismprovided in a magnetic head assembly. FIGS. 5A, 5B give top views andcross sections of a magnetic head assembly mounted on two types ofturntables, one with an edge 15h (FIG. 5A) and the other without it(FIG. 5B). The top view and the cross section given in FIG. 5Aillustrate the method of mounting magnetic head on turntable 15 withflying type sliders 23c and 23d connected to two long arm springs 30aand 30b, respectively. FIG. 5B shows the top view and the cross sectionof magnetic head mounted on edgeless turntable 15. The magnetic headassemblies are composed of two flying-type sliders connected to long armsprings 30a and 30b.

The distance from the center of the head gap of magnetic head 13a to thecenter of rotation shaft 16 equals that from the center of the head gapof magnetic head 13b to the center of the rotation shaft. The line thatruns straight through the center of each gap must pass the center ofrotation shaft 16. The long arm springs are screwed or adhered on oneend closer to the rotation shaft.

The outer ends of the long arm springs are secured in flying-typesliders 23c and 23d with a flexure (not shown). The long arm springshave projections 32a and 32b further outside of flying-type sliders 23cand 23d. These two projections 32a and 32b control the upward motion ofthe long arm springs by means of cylindrical stoppers, which in FIG. 5Aare represented as reverse L shaped stoppers 33a and 33b, just insideedge 15h of the turntable. The surfaces of flying type sliders 23c and23d are set slightly higher than the edge of the turntable as shown inFIG. 5A. When a magnetic card has been inserted into the magnetic cardreader, the magnetic head assembly will be set inside carriage base 189.As the pressure pad presses the magnetic card downward, the surfaces offlying type sliders 23c and 23d are pushed down by the magnetic card. Atthis point, projections 32a and 32b leave stoppers 33a and 33b for alower position, thus functioning as a leaf spring that performs up anddown movement. The long arm springs therefore work as a cantileverspring, e.g., their outward motion is limited within a certain range bythe two stoppers even if their elasticity has been reinforced.

FIG. 5B shows an example of using flat, edgeless turntable 15. Rotarytransformer holder 20 is modified to make its outmost part elongatedupward, thus forming edge 20h. Edge 20h is secured on apparatus base 21.Attaching reverse L shaped stoppers thoroughly inside the rotarytransformer holder will produce the same effect as the above example.Because a magnetic card is pressed against the surfaces of the flyingtype sliders, however, the clearance between the reverse L shapedstoppers and the projections becomes minuscule. It could result in acontact accident. To deal with this problem, U-shaped stoppers are setto the turntable instead of the above reverse L-shaped ones. That is,stoppers 34a and 34b attached to turntable 15 rotates together withmagnetic heads 13a and 13b, which eliminates the risk of causing acontact accident between the stoppers and the projections.

The stoppers and projections employed for the long arm springs areunnecessary if a gimbal spring is applied.

Embodiment 6

This embodiment gives methods of cleaning magnetic heads, and preventingdirt, dust or contaminants from being accumulated on a turntable bymaking the best of air flow. FIGS. 6A to 6C illustrate the structure ofa magnetic head assembly equipped with louvers and a cleaner onturntable 15 or on rotary transformer holder 20. FIG. 6A shows inletholes 35 provided on base 15g of the turntable and outlet holes 36located on the edge 15h. By contrast, FIG. 6B shows inlet holes 35 onbase 15g of the turntable and outlet holes 37 located on edge 20h of therotary transformer holder. In either case, magnetic heads 13a and 13bslide on the surface of a magnetic card to access data on the tracks.Magnetic powder, dust or dirt produced during contact or dirt orcontaminants brought into the apparatus from outside could beaccumulated on the turntable.

Removal of dirt, dust or contaminants from the turntable 15 involves thetheory of air pressure. Air pressure at the center of a rotating bodyremains low while it is higher near the edge. As an inserted magneticcard travels over the magnetic head assemblies, the inside of theapparatus becomes airtight except a tiny clearance between the magneticcard and edge of the turntable 15. This holds true for both examples inFIG. 1 and FIG. 2.

The most effective method can be to let a larger amount of air flow infrom beneath the turntable 15 by providing several inlet holes 35 aroundrotation shaft 16 of the turntable 15. The air is then exhausted throughoutlet holes 36 on the edge of the turntable or of outlets 37 on theedge of the rotary transformer holder 20. The dust or dirt that may haveresidued inside the turntable 15 can be removed in this way. Althoughthe size of these outlet holes is arbitrary, it would be more effectiveto make them larger. The outlet holes presented in this example arerectangular. To prevent foreign matters from flowing in along with theair, an air filter of coarse cloth can be attached to the inlet holes.Any contaminants of substantial size can be stopped there.

FIG. 6C illustrates a more powerful method of removing dirt or dustattached to a magnetic card la and magnetic powders or contaminants thatare produced during contact. Cleaner 38 using a cloth liner is attachedto the section designated with oblique lines on the base of theturntable 15, in between two magnetic heads 13a and 13b. This type ofliner has come to be widely used inside a cartridge for 3"5 floppydisks, so as to make a light contact with the surface of magneticrecording media.

In case of Embodiment 1 in FIG. 1, it is desirable to set the cleaner 38in such a way it slightly touches the surface of a magnetic card 1a whenthe pressure pad pushes down on it. The cleaner can also be applied toEmbodiment 2 in FIG. 2 provided that the cleaner does not touch rotarytransformer holder 20 that surrounds the turntable 15.

It is highly recommended that the cleaner 38 be detachable to replace itwith a new one for wear after repeated use. Attaching a cleaner 38 tothe turntable 15 using screws is one possible way.

This example can be applied not only to magnetic card readers but alsoto optical card readers which is discussed later.

Embodiment 7

Embodiment 7 describes the structure of a rotary transformer which isindispensable to a magnetic head assembly.

The diagrams shown in FIGS. 7A to 7C and in FIGS. 8A to 8C representcross sections of a rotary transformer mounted on a magnetic cardreader.

FIG. 7A represents an example of using rotary transformer 39 dividedinto two parts. One is primary core 39a secured onto apparatus base 21and the other is secondary core 39b which is attached to the back ofturntable 15.

Both primary core 39a and secondary core 39b are the disks made ofmagnetic materials such as ferrite. Formed on the surface of primarycore 39a are two concentric winding grooves 39c and 39d. Also, twoconcentric winding grooves 39e and 39f are formed on the surface ofsecondary core 39b directly facing the surface of the primary core.These four wire-wound grooves are the basics of a transformer. Thetheory of a rotary transformer is explained in greater detail later withreference to FIGS. 9A to 9C.

This type of transformer can be characterized in that signals can besent and received between windings physically separated to primary core39a and to secondary core 39b. It is typically applied to such apparatusas a video tape recorder (VTR).

Recording current or reproducing signals are transmitted between twomagnetic heads 13a and 13b on turntable 15 and the read and writecircuits on a magnetic card reader via the above mentioned windings.Although secondary core 39b in FIG. 7A is using up the whole space backof the turntable 15, it can be arranged near the edge of the turntable15 to provide inlet holes 35 around the rotation shaft 16 as shown inFIG. 6A and 6B.

Another advantage of a divided rotary transformer is that the height canbe lower.

Supported by bearing 31 attached to apparatus base 21, rotation shaft 16of turntable 15 rotates with rotor 22b of DC motor 22. When phasecurrent reaches driving coil 22c of stator 22a, magnetic fields aregenerated toward magnet 22d of rotor 22b. Because the magnet has beenalready magnetized circumferentially, magnetic flux leaked from thesemagnetic circuits of the motors may affect the signaling circuit ofrotary transformer 39. To shield magnetism, iron is used for theapparatus base 21, and magnetic material or iron is used for theturntable 15 and the rotary transformer holder 20 to shield leakageflux. Although not shown in this example, different types of shieldingcan be added to space 40s created inside the turntable 15.

FIG. 7B shows a method of shielding the turntable 15 having edge 15h. Acylindrical rotary transformer 40 is set around rotation shaft 16.Secondary core 40a concentrically rotates with the rotation shaft 16,whereas primary core 40b is secured on fixed stand 40c. A rotarytransformer according to this example can be smaller in its diameter butmust be higher in its height compared to the example in FIG. 7A. Inaddition, providing an edge both under 15i and on 15h of the turntable15 will dispense with a rotary transformer holder 20.

FIG. 7C illustrates cylindrical rotary transformer 41 set around theturntable 15 having edge 15h. Primary core 41a is wound around edge 15hof the turntable 15 and secondary core 41b is mounted on fixed stand41c. This example is advantageous in that the apparatus can be shortenedbecause rotary transformer 41 can be set as high as the turntable 15.Iron is used for apparatus base 21 to shield magnetism. It is possibleto add some new shielding to space 41s under the turntable.

FIGS. 8A and 8B show flat turntable 15 surrounded by rotary transformerholder 20. The rotary transformer shown in FIG. 8A is the same as theone presented in FIG. 7A. It is divided into two parts: one is primarycore 39a secured on apparatus base 21 and the other is secondary core39b attached to the back of turntable 15. Although secondary core 39b isdesigned to use up the whole space under the turntable 15, it can bearranged toward the end of the turntable 15 to provide inlet holes 35near rotation shaft 16.

The dual-type rotary transformer 39 of this example renders theapparatus shorter, and therefore, more compact. Iron can be used for theapparatus base 21, and iron or magnetic material can be used for theturntable 15 and the rotary transformer holder 20 to shield leakageflux.

FIG. 8B shows flat turntable 15 and cylindrical rotary transformer 40around rotation shaft 16. Primary core 40a is set to concentricallyrotate with the rotation shaft 16 whereas secondary core 40b is mountedon fixed stand 40c. The diameter of this type of a rotary transformer 40can be shortened. The characteristics of magnetic shielding is the sameas those explained in FIG. 7B.

The example given in FIG. 8C is analogous to that of FIG. 7C, in thatprimary core 42a is incorporated into rotary transformer holder 20 andsecondary core 42b is set under the turntable 15. Although it is notshown in this diagram, it is also possible to set the secondary core tothe edge of the turntable 15.

For the card reader of the present invention, a rectangular magneticcard supported by a pad travels to the head assembly. The head, whichwrites data on the recording tracks or reads data from it, transmits theread and write signals via the rotary transformer.

Moreover, the leakage flux from the driving motor of the head assemblyis shielded, thereby eliminating any irregular, unwanted damage duringdata read and write.

Embodiment 8

With reference now to FIG. 9, the operation and the circuitry of arotary transformer are described in detail hereinbelow.

FIG. 9A gives the basic concepts of a transformer. The transformerconsists of a magnetic material referred to as iron core 43 and twowindings wound separately on it. Of the two, the winding connected topower source is called the primary winding or primary coil 44. Thewinding connected to load is called the secondary winding or secondarycoil 45.

When the terminal of secondary winding 45 is open, an alternatingcurrent generates magnetomotive force as it runs through the primarywinding, thereupon generating magnetic flux within the iron core. Themagnetic flux also alternates simultaneously with alternating current.The ratio between the electromotive forces that induce electricity tothe primary winding e₁ and to the secondary winding e₂ is given, if lossis ignored, by the equation

    e.sub.1 /e.sub.2 =E.sub.1 /E.sub.2 =n.sub.1 /n.sub.2 =a    (1)

where, n₁ and n₂ denote the number of turns of the primary winding andthe number of turns of the secondary winding, respectively.

E₁ and E₂ in the above equation indicate the primary induction voltageand the secondary induction voltage. They are the effective values of e₁and e₂, respectively, and "a" denotes the ratio of the number of turnsbetween the primary and secondary windings. Clearly, the inductionelectromotive force ratio equals the number of turns ratio. Current doesnot flow through the primary winding unless the primary supply voltageV₁ (the effective value of the alternating current) is supplied to theprimary winding. Because the primary supply voltage V₁ roughly equalsthe primary induction voltage E₁, the ratio between the primary supplyvoltage V₁ and the secondary load voltage V₂ is obtained by

    V.sub.1 /V.sub.2 =E.sub.1 /E.sub.2 =n.sub.1 /n.sub.2 =a    (2)

Voltage is thus transformed based on the number of turns ratio.

FIG. 9B shows a shell-type transformer commonly used for a power sourceor communications equipment. The transformer has a structure in whichthe primary and secondary windings 46a, 46b are layered and an iron core43 is formed around the primary and secondary windings 46a, 46b.

FIG. 9C shows the basic structure of a shell-type rotary transformer 48,consisting of primary core 43a and secondary core 43b. Looped in acircle, the windings 46a and 46b are covered up entirely. The primarycore 43a and the secondary core 43b in this diagram correspond toprimary core 39a and secondary core 39b shown in FIG. 7A. The twogrooves, groove 39c on the primary core 39a and groove 39e on thesecondary core 39b, are formed so as to exactly face each other. Thewindings are applied to these upper and lower grooves (39c, 39e), whichcorrespond to the above-mentioned windings 46a and 46b.

FIGS. 10A to 10C are the equivalent circuits of a transformer, where L₁and L₂ denote leakage inductance and M denotes excitation inductance.The equivalent circuit in FIG. 10A has four terminals. FIG. 10Bindicates an equivalent circuit for write operation. Signal source e_(S)is connected to the primary winding and load impedance Z_(L) isconnected to the secondary winding of the equivalent circuit in FIG.10A. Z_(S) here denotes the internal impedance of signal source e_(S).The current i_(L) in the load can be obtained by the expressions

    i.sub.L =e.sub.S ·Z.sub.M /(Z.sub.1 ·Z.sub.2 +Z.sub.1 ·Z.sub.M +Z.sub.2 ·Z.sub.M)             (3)

    Z.sub.1 =Z.sub.S +jωL.sub.1                          (4)

    Z.sub.2 =Z.sub.L +jωL.sub.2                          (5)

    Z.sub.M =jωL.sub.M                                   (6)

Being frequency dependent, the transmission characteristics aredetermined by the values of Z₁, Z₂, and Z_(M). However, only analternating signal is transmitted because the real part of Z_(M) is nullor almost negligible.

FIG. 10C is an equivalent circuit for data read. Signal source e_(H) isconnected to the primary winding and load Z_(R) is connected to thesecondary winding. Voltage e_(R) at the ends of the reproducing loadZ_(R) is then given by

    e.sub.R =e.sub.H ·Z.sub.R /(Z.sub.1 ·Z.sub.2 +Z.sub.1 ·Z.sub.M +Z.sub.2 Z.sub.M)                       (7)

The transmission characteristics in this case are also highly frequencydependent, thus resulting in transmitting only alternating signals.

FIG. 10D gives the fundamentals of read/write circuit configuration fora magnetic card reader in accordance with the present invention.Magnetic head 13a or 13b is connected to secondary winding 46b of rotarytransformer 48 while primary winding 46a is connected to read/writecircuit 53. (Explanation of magnetic head components such as terminatingresistors is omitted here.) The read/write circuit is connected tosignal processor 54. Signal processor 54 converts data (mostly NonReturn to Zero data) input via an interface connector and clock signalsinto modulation code such as Modified Frequency Modulation (MFM), 2-7Run Length Limited code (RLL), 1-7 RLL, or PRML by means of the internalmodulation circuit. The converted modulation code is then output to theread/write circuit 53. Conversely, the signal processor demodulates themodulation code sent from the read/write circuit 53 to the original NRZdata and clock signals.

Upon receiving the modulation code from signal processor 54, theread/write circuit 53 converts the code into a write current pulsebefore sending it to primary winding 46a. From the primary winding 46a,the pulse, which is output as the read signal, further passes through anamplifier, low-pass filter, and differentiator, to output the signalsconverted to the modulation code to signal processor 54.

In the above example, in which read signal from magnetic head 13a or 13bis directly input to read/write circuit 53 via secondary winding 46b andprimary winding 46a, noise from the DC motor 22 shown in FIGS. 7A to 8Cor mechanical noise outside a magnetic card reader can enter the pathbetween magnetic heads 13a or 13b and the read/write circuit 53.

Thus, FIG. 10E shows another example of circuitry where amplifier 53a isinstalled between magnetic head 13a or 13b and secondary winding 46b. Agreatly amplified read signal is input to the amplifier inside theread/write circuit 53 through rotary transformer 48. Amplifier 53a isactivated by positive direct current DC voltage supplied from powersource. However, it cannot be powered via cable because it is mounted onthe turntable 15 shown in FIGS. 7A to 8C along with magnetic heads 13aand 13b. Hence, it is necessary to provide a new supply method using arotary transformer.

Rotary transformer 48 in FIG. 10E therefore is augmented with newprimary winding 55a and secondary winding 55b. The primary winding 55ais connected to DC-AC converter 56 that converts direct current intoalternating current, and secondary winding 55b is connected to AC-DCconverter 57 which converts alternating current into direct current. Thepositive DC voltage generated at AC-DC converter 57 is then supplied toamplifier 53a.

Depending upon the capacity of the power supply and the circuitconfiguration, the read/write circuit 53 can, entirely or partially, bemounted on the turntable 15 with an amplifier 53a.

Embodiment 9

FIGS. 11A and 11B show a primary concept of a magnetic head. There aretwo types of magnetic heads for a magnetic card reader. One is designedonly to read the data stored on a magnetic card while the other servesfor both data reading and writing. In using only one magnetic head, adummy magnetic head can be also mounted on the turntable 15 to preventthe turntable 15 from making irregular rotation. The dummy magnetic head13b, being identical in its size and shape, is placed to counterbalancethe actual magnetic head. Thus electrically flawed magnetic heads can beused as dummy heads, provided that the mechanical properties are normal.Or a balancer that counterweighs the actual magnetic head and thatproduces friction equivalent to that between the actual magnetic headand a magnetic card 1a can be utilized.

In mounting two magnetic heads on the turntable, they must be aligned insuch a way that the distance from the center of each head gap to therotation pivot must be exactly the same on the linear line that passesthrough the center of the rotation shaft 16. To be precise, there mustbe no eccentricity at the rotation shaft 16, and the center of loci onthe recording tracks made by the two magnetic heads on a magnetic card1a must be the same.

The possible functions of two magnetic heads to be mounted arethreefold: both magnetic heads 13a, 13b are capable of data reading andwriting, one is for data read and the other for data write, and both twoare for data read.

With reference now to FIGS. 11A and 11B, the basic concept of a magnetichead and the loci of recording tracks of the present invention isdescribed hereinbelow. Ring-shaped magnetic head 58 (magnetic heads 13aand 13b in FIG. 1) has head gap 60 at one end of its head core 59,around which head coil 61 is wound.

When a write current pulse output from read/write circuit 53 in FIGS.10D and 10E to "terminal a" through "terminal b" of head coil 61 viarotary transformer 48 generates magnetic flux at head gap 60, data writeis performed on recording medium 62. In this example, magnetic head 58is fixed while magnetic medium 62 travels in the direction of arrow F ata predetermined speed. When data has been continuously written,recording track 63 equivalent in its width to the head gap (L) isformed. Although the recording track becomes actually slightly widerthan the head gap, the details are omitted.

FIG. 11B demonstrates the loci formed on the recording tracks when amagnetic head rotates with rotation shaft 16 as the pivot. Diagram (1)depicts a locus made when only one magnetic head 13a performs datareading and writing, e.g., the other one 13b is a dummy magnetic head. Agood magnetic head 13b can be used as a dummy head for backup if theactual magnetic head 13a should electrically fail for some reason.However, to achieve this method, circuitry necessary for data read andwrite, including a rotary transformer, must be readily available. Thejudgement of failure occurrence and the switching of magnetic heads aremade by a control circuit (not shown) outside of the magnetic cardreader.

Diagram (2) indicates that two magnetic heads 13a and 13b perform dataread and write. In this method, it is imperative that the gap width,length, and the inclination against recording tracks be identical forboth magnetic heads 13a and 13b. This method is advantageous in reducingrotational delay over the previous method, because data can be writtenin or read from with a magnetic head located closer to a particularsector on the tracks to be accessed. Moreover, two magnetic heads rendersimultaneous recording possible, and in addition, the data written withone magnetic head can be read by the other in half-a-turn wait insteadof one full turn of the tracks.

Diagram (3) depicts the dual-purpose thin-film heads used for hard diskunits. They are two-in-one type of magnetic heads consisting of awrite-only thin-film head and a read-only thin-film head. The head core59, head gap 60, and head coil 61 of the write-only thin-film head aremade of thin films and those of the read-only thin-film head are made ofmagnetoresistance effect elements (hereinafter referred to as the MRhead). The width of the magnetoresistance effect element (sensor width)of the MR head is set narrower than the gap width of the write-onlyhead. If the maximum gap width of the write-only thin-film head isL_(W1) +α, minimum width L_(W1), the maximum sensor width of the MR headis L_(W2) +β, its minimum width is L_(W2), the maximum deviation betweenthe two thin-film heads is γ, the maximum error from the center of adesirable track obtained by adding the estimated error from the pivot oftwo thin-film heads, track deviation of the recording medium due totemperature and humidity characteristics, and rotational precision is δ,and the central distance from one track to the next track is L_(p), thenthe expressions of applicable conditions will be

    L.sub.W1 +α+δ+<=L.sub.p                        (8)

    (L.sub.W2 +β+γ)/2+δ<=L.sub.W1 /2          (9)

In the worst case, the loci on two adjoining tracks may overlap. Thisdoes not pose any problem because data on the overlapped loci will notbe read due to narrow sensor width of the MR head.

Diagram (4) represents two magnetic heads, of which 13a is write-onlyand 13b is read-only. The expressions (8), (9) of applicable conditionsgiven in the previous example hold true here as well. The conditionalrequirement is somewhat more flexible compared to the above example ofdiagram (2), where the magnetic heads must have exactly identical headgaps. In addition to the thin-film write-only magnetic heads and MRread-only magnetic heads, conventional ferrite magnetic heads will wellserve the purpose for both write-only and read-only magnetic heads. Whena recording medium with high magnetism is used, a MIG head can be usedto reduce the flux saturation at the end of a magnetic head gap byapplying a highly permeable thin-film substance to the gap of thewrite-only and read-only magnetic heads.

Embodiment 10

In conventional magnetic disk units, including hard disk or floppy diskdrive units, data is written in or read from the tracks of a recordingmedium which rotates at a predetermined speed, forming concentric tracksat an equal pitch. High track density and high bit density are the keysto expanding the storage capacity. The former is achieved by increasingthe number of recording tracks per recording medium by narrowing trackpitch and track width, whereas the latter is achieved by increasing datarecording capability per track.

Except for the MR heads previously discussed, when a conventionalmagnetic head is used as a read head, the reproduction output voltagedepends logically on the rotational speed of the recording mediumrelative to that of a magnetic head. More specifically, the reproductionoutput voltage increases towards the outside tracks while it reducestowards the inside tracks due to the lowering relative speed. Thereliability of data reproduced with a magnetic disk unit is typicallyexpressed with the error rate, up at least to 10⁻⁹. However, to obtainthe error rate, the ratio between the signal and noise (S/N), e.g.,mechanical noise or medium noise versus reproduction output voltage,must be 28 decibels or more. Thus the upper limits of the track densityand bit density will be determined at the innermost track, where theratio between the noise and signal is the hardest to obtain. Further,writing data at a preset clock frequency on a recording medium rotatingat a certain speed causes the bit density to be higher on the insidetracks than on the outside tracks.

For the magnetic card reader of this invention, the relative speedbetween the magnetic head and recording medium can be kept consistentirrespective of the positions of tracks, thus enabling data to bereproduced from any tracks on a magnetic card with high reliability.

Referring now to FIGS. 12A to 12C, the method of storing data on amagnetic card according to the present invention is described. FIG. 12Ashows a locus of a track formed with either one or two magnetic headswhen data is written on the surface of a recording medium, magnetic card1a. The center of revolution of both magnetic heads 13a and 13b mustpass the horizontal center line (X-Y) of a magnetic card 1a. Inaddition, radius R of recording track 63 is set to be less than half ofthe vertical length of a magnetic card.

The reason for setting the radius R of a recording track less than halfthe vertical length of a magnetic card can be explained by the width ofcard side guide 187, card support guides 187a and 187b attached to acarriage base 189 of feeding mechanism 186, which will be discussedlater with FIGS. 27A to 27C. It is also preferable not to use the wholearea of a magnetic card as the recording surface, for the ends of a cardcan be damaged or contaminated when handled with hands.

FIG. 12B illustrates recording tracks with radius R by moving magnetichead leftward relative to magnetic card 1a at the same pitch (P). Whenmultiple recording tracks have been formed, technically non-readableareas A and B are created both at the top and the bottom of the magneticcard.

FIG. 12C is a magnified diagram of center lines 63a and 63b of twoadjoining recording tracks. As a magnetic head moves farther from thehorizontal center line X-Y, the center lines 63a and 63b on therecording tracks come closer to each other, finally intersecting. Whentwo tracks come closer to each other, crosstalk, a phenomenon in which amagnetic head picks up signals from the adjoining track, occurs, therebyreproducing incorrect data.

Let X denote the space between tracks and a the angle from horizontalline X-Y. Then the larger the angle a grows, the narrower the space Xbetween the tracks becomes by the expression

    X=P·cos α                                   (10)

Track pitch P is then obtained by

    P=X/cos α                                            (11)

FIG. 13 shows the loci of leftmost and rightmost tracks recorded on amagnetic card (the use of an optical card will be described later). LetI denote the distance between the centers of tracks 0₁ and 0₂, and L_(t)the length of recording tracks on a recording surface, and N the numberof tracks, then the total track length is determined by the equations

    L.sub.t =2πR·2 α/2π=2 αR        (12)

    N=2I/P=2I cos α/X                                    (13)

    M=2αR·2I cosa/X

     =4RI/X·αcos α                        (14)

Note that α is indicated by a radian.

From expressions (12) through (14), the most effective way of maximizingM is to maximize "α·cos α" of expression (14). Then the result of FIG.14 is obtained by the expression

    Z=α·cos α                             (15)

To get at least 95% of efficiency rate, a is within the range from 0.7to 1.0, e.g., in 40 to 57.3° degrees in angle.

Embodiment 11

For a hard disk unit or floppy disk drive unit, a single magnetic headwrites on or reads data from a recording medium, normally making amagnetized pattern of the recording tracks at a right angle to thecenter line of the tracks.

On the other hand, the azimuth recording method is applied to magnetictape units. The azimuth recording is characterized in each track angledin the magnetization direction. This logically leads to the conclusionthat the crosstalk between the adjoining tracks can be minimized whenthe angle of the magnetized patterns is 90 degrees to each other.

With two magnetic heads being available, the recording method of makingeach track having an azimuth angle is achieved for the presentinvention. The magnetic heads shown in (2) or (3) in FIG. 11B can beused for the magnetic heads. In using magnetic heads of (2), forexample, head gap G1 of magnetic head 13a, which would be placed at aright angle from the center line of recording tracks, is angled at -θdegrees from the center lines of the recording tracks and head gap G2 ofmagnetic head 13b is at +θ degrees to write data with a singlerepetitive current.

Referring now to FIG. 15A, the magnetized status of track 64 recordedwith magnetic head 13a is indicated. FIG. 15B, on the other hand, showsthe magnetized status of track 65 recorded with magnetic head 13b.Azimuth recording allows two magnetic heads 13a and 13b to write or readdata alternately for every single track.

FIG. 15C shows two magnetized recording tracks 64 and 65 on a magneticcard, one on the right and the other on the left. Recording track 65shown in FIG. 15B is placed to the left of recording track 64 shown inFIG. 65A by one track pitch, leaving out the top and bottom portionswhere the tracks intersect. Although not indicated in the figure, afterone magnetic head carries out data writing for one track, it alternateswith the other magnetic head which continues data writing for the nexttrack. The fact that two magnetic heads alternate data writing with eachother makes it possible to magnetize two adjoining recording tracks inthe direction of 2θ azimuth angle when compared with the techniques inthe prior art. Which, in turn, forms a right angle azimuth byanglulating each head gap of the two magnetic heads by +45 and -45degrees.

Setting two magnetic heads by half a track instead of a full track isanother possible method of producing azimuth on the adjoining tracksbetween two track groups formed on the left and right sides on amagnetic card. Head gaps of the two magnetic heads shown in (2) and (3)of FIG. 11B angulated at different degrees can also read or write dataalternately by half a track or by a full track. However, data writtenwith magnetic head 13a cannot be read with magnetic head 13b. Byextension, if data written with magnetic head 13a is overwritten withmagnetic head 13b for modification, magnetic head 13a fails to read theoverwritten data. Data read is enabled only with the same magnetic headthat actually wrote the data or with a magnetic head having a magneticgap of exactly the same angle. This prohibits the magnetic heads shownat (4) in FIG. 11B from achieving azimuth recording of the presentinvention.

The azimuth recording enables the number of tracks to be increasedbecause track pitches can be made smaller than conventional recording,which, in turn, increases storage capacity of magnetic cardssignificantly.

Embodiment 12

Embodiment 12 discusses the methods of applying the present invention toan optical card, and further, to an optical head.

An optical card reader is different from a magnetic card reader in itshead structure and its recording medium. With optical cards, data can bestored either on a single side or on both sides. When data is to bestored on both sides, two optical heads can be employed, one on thefront and the other on the back of the optical card, to simultaneouslyaccess data. Or the optical card can be reversed when only one opticalhead is employed.

FIGS. 16A to 16C illustrate the cross sections of an optical card.Besides those recording media designed for optical disk units, there areseveral other types of available media, such as those for compact disks(CDS), video disks (VDs), write-once (WOs), re-writable phase-modifiersand magneto-optic (MO). Despite the fact that these recording media arebased on the same structure, they may differ slightly in their features.Most notably, the magneto-optic recording, which has already been inextensive use, differs from other structures in that an electromagnetmust be set on the back of optical card 150 as a magnetization bias.

FIG. 16A represents a cross section of a read-only optical card 150,consisting of light transmission layer 150a, on which are placedreflecting film 150b and protective board 150c. The light transmissionlayer is usually an opaque plastic whereas the reflecting film is madeof aluminum. Laser lights emitted from inside optical head 151 (notshown) are converged at objective lens 151a and irradiated to reflectivefilm 150b. Data, which has been stored in concave pits and in the spacesbetween the pits, is converted into electric signals in the optical headas the amount of the reflected light changes.

FIG. 16B is a cross section of a write-once optical card. One way ofwriting data is to make holes (pits) on a recording film with the laserlights. Data is then read by converting the presence or absence of pitsdetected by the laser lights into electric signals. Another way of datatransmission is to cause material change upon the irradiated part. Thematerial is then changed into a thin film as its reflection ratechanges. On the base of light transmission layer 150a, the write-onceoptical card is formed in the order of protective layer 150d, opticalrecording layer 150e, protective layer 150f, and protective board 150c.

FIG. 16C is a cross section of an optical card made of an opticalmagnetic medium. With light transmission layer 150a as the base, it isformed in the order of protective layer 150d, magneto-optic recordinglayer 150g, protective layer 150f, and protective board 150c. The laserlights emitted from inside optical head 151 (not shown) are converged atobjective lens 151a and then irradiated on magneto-optic recording layer150g. By applying reverse-magnetic fields to the medium magnetized inone direction, magneto-optic recording uses laser lights with which themedium is magnetized in the direction of applied magnetic fields nearthe Curie point. For data read, based on the Kerr effect or Faradayeffect, the polarized light is irradiated upon the recording mediumwhich slightly polarizes the surface depending on the magnetizeddirection, which is then converted into electric signals.

Embodiment 13

Embodiment 13 will give a general description of the structure of thehead assembly of an optical card reader.

FIGS. 17A and 17B show the structure of data read and write mechanism ofthe optical card reader. In FIG. 17A, objective lenses 151a and 151b ofone or two optical head 151 (not shown) are attached on turntable 15.Being linked with rotation shaft 16 of motor 22 just as the onepresented for a magnetic card reader shown in FIG. 2, the turntablerotates in the direction of arrow C at a predetermined speed. Turntablespacer ring 152 prevents foreign matter from entering and keeps acertain distance between objective lenses 151a and 151b on the turntable15 and optical card 150.

FIG. 17B shows a head assembly equipped with a cleaning mechanism madeof cloth or soft brush so as not to damage the surface of an opticalcard. The cleaner continuously contacts light transmission layer 150a onthe back of the optical card as the turntable rotates. Although notincluded in this embodiment, it is possible to have inlet holes 35 andoutlet holes 38 used for the turntable 15 and rotary transformer holder20 shown in FIGS. 6A and 6B for turntable 15 and turntable spacer ring152.

Embodiment 14

With reference now to FIGS. 18A and 18B and 19, the structure of theoptical head assembly of the present invention is set forth in detailbelow.

The read and write mechanism of an optical card reader and a magneticcard reader shown in FIG. 8A are similar in their basic structures. Formagnetic card reader, stored data is converted into electric signal withthe magnetic heads 13a and 13b, and then picked up with the rotarytransformer 39 in an untouched manner.

With an optical card reader, however, the laser beam from a laser diodein the optical head 151 must be transmitted to the objective lenses 151aand 151b on the turntable 15 through optical path. To read data, lightsignals must be transmitted to the optical sensor to be converted intoelectric signals. It is prohibited to put anything that could interruptlight transmission in the optical path.

To solve the above problem, rotation shaft 16 both on and under theturntable 15 and the center of rotor 22b of the DC motor 22 are madehollow to form an optical path. FIG. 18A gives an example of using oneobjective lens 151a on the turntable 15. In FIG. 18A, the laser beamemitted from laser diode 151c passes through collimator lens 151d,polarization beam splitter (PBS) 151e, and λ/4 plate 151f (λ being awavelength). Then laser beam is bent at reflecting mirrors 151g and 151hplaced on the upper hollow of the rotation shaft 16 and converged byobjective lens 151a to be irradiated upon reflective film 150b oroptical recording layer 150e.

Reflected light then passes back to objective lens 151a, reflectivemirrors 151g and 151h, hollow parts of rotation shaft 16, λ/4 plate151f, and polarization beam splitter 151e to be converted into electricsignals by optical sensor 151i.

FIG. 18B gives an example of using two objective lenses. When thewavelength of the laser beam emitted from laser diode 151c is assumed tobe λ₁, the wavelength of the laser beam from laser diode 151j is assumedto be λ₂.

Emitted from laser diode 151c, the laser beam passes through collimatorlens 151d, half mirror 151k, polarization beam splitter 151e, and λ/4plate 151f. Then the laser beam is bent first at dichroic prism 151lplaced in the upper hollow of rotation shaft 16 and at reflectingmirrors 151g and 151h, and then converged by objective lens 151a to beirradiated upon reflecting film 150b or optical recording layer 150e ofthe optical card. The laser beam emitted from laser diode 151j passesthrough collimator lens 151m, half mirror 151k, polarization beamsplitter 151e, and λ/4 plate 151f. Then it is reflected by dichroicprism 151l placed at the upper hollow in rotation shaft 16 and bent byreflecting mirror 151n, and converted by objective lens 151b, to beirradiated by reflecting film 150b or optical recording layer 150e ofthe optical card.

The dichroic prism 151l is characterized in that it passes all lightfrequencies except those for the color which the prism is designed toreflect. Thus, in this example, the laser light with wavelength λ₁ fromlaser diode 151c is passed while the laser beam from laser diode 151j,whose wavelength is not designed to pass, will be reflected. Inaddition, another polarization beam splitter can be arranged above PBS151e in order to input the laser beam emitted from collimator lens 151m.

The light reflected from the reflecting film or optical recording layerof the optical card, then passes through objective lens 151a, reflectingmirrors 151h and 151g, dichroic prism 151l, the hollow in rotation shaft16, λ/4 plate 151f, polarization beam splitter 151e, and dichroic prism151p to reflecting mirror 151q to be finally converted into an electricsignal by optical sensor 151i. Meanwhile, the light that reflected atobjective lens 151b passes through reflecting mirror 151h, dichroicprism 151l, the hollow part in rotation shaft 16, λ/4 plate 151f, topolarization beam splitter 151e, and then is reflected by dichroic prism151p to be converted into an electric signal with optical sensor 151s.

FIG. 19 presents another example of the optical head assembly of thepresent invention. The components such as the λ/4 plate 151f andpolarization beam splitter 151e must be installed close to the rotor 22bof DC motor 22 to pass laser beam straight to the hollow made inside therotation shaft 16. However, they may not be mounted in a desiredposition due to the limitations from the height of the optical cardreader or from some installation constraints. Thus, collimator lens 151tis placed under the hollowed rotation shaft 16 so that the light can bedirectly sent to the λ/4 plate 151f using flexible optical fiber 151u.Combining the collimator lens 151t and optical fiber 151u enables theabove-mentioned components to be mounted in a desired place.

Embodiment 15

In magneto-optic recording, reverse magnetic fields are applied to themedium magnetized in one direction, and the medium is magnetized in thedirection of applied magnetic fields when it close to the Curie point asit is irradiated with laser beams. Generally, on the side opposite tothe recording surface, a magnet for magnetization bias is lifted to beplaced on the objective lens of the optical head across the optical diskmedium to resonate with the optical head that seeks on the optical diskmedium rotating at high speed. However, because the optical head rotatesand the recording medium stays or moves in a horizontal direction in thepresent invention, conventional magneto-optic recording is difficult toapply to the present invention.

FIG. 20A illustrates one example of solving the above problem. Whencurrent is sent to cylindrically wound coils 151v and 151w on objectivelenses 151a and 151b on the turntable 15, magnetic flux is producedtoward the center line of the objective lenses 151a, 151b. Then magneticfields are added at a right angle to the parts irradiated with laserbeam on the magneto-optic recording layer 150g of optical card 150. Thecurrent will be supplied from outside the turntable 15 using secondarycore 41a and primary core 41b of the rotary transformer 41 shown in FIG.7C.

To be precise, alternating current output from the DC-AC converter ofthe optical card reader is sent to the wiring of the secondary core 41a,and the alternating induction current generated at the primary core 41bis converted into direct current with the circuits incorporated on theturntable 15. The circuits are set separately on the turntable 15. Thedirection of the current through coils 151a and 151b dictates thedirection of magnetic fields being generated. When laser lightsirradiates, the data to be stored on the magneto-optic recording layer150 will be magnetized either upward or downward of the magneticsurface. Therefore, the rotary transformer 41 must be provided with twowirings: one for power source and the other for the signals thatindicate the direction of the current and the switching time.

FIG. 20B gives the overview of the turntable discussed in FIG. 20A.

FIG. 21A indicates magnetic fields generated when current passes throughcoil 151v. The magnetic flux crosses almost at a right angle at thecenter of the coil 151v where the laser beam on the magneto-opticrecording layer 150 are converged.

FIG. 21B shows thin iron or magnetic plate 154 added close tomagneto-optic recording layer 150. The magnetic flux generated from coil151v can return to coil 151v through the thin plate 154 without beingdiffused. Furthermore, magnetic flux will cross nearer to a right anglewhere the laser beam of the magneto-optic recording layer is converged.

Embodiment 16

Referring now to FIGS. 22A to 22C and FIGS. 23A, 23B, the types andstructure of magnetic cards will be discussed below.

The medium shown by the oblique lines in FIGS. 22A to 22C indicatesreflecting film 150b or optical recording layer 150e or magneto-opticrecording layer 150g. The reason the film or the layer does not coverthe entire optical card 150 is that the scope to be used as recordingtracks is limited as explained in FIGS. 12B and 12C when the rotationaloptical head is applied. The margins, where recording tracks intersect,cannot be used. Although only three types of optical cards given in FIG.22 are available, it is also possible to make the whole surface as therecording layer.

FIG. 23A shows the structure of optical cards. Optical cards describedin FIGS. 22A to 22C are layered as illustrated in FIGS. 16A to 16C. Ifit is necessary to add more material to reinforce the mechanicalstrength of optical card 150, recording medium 157b shown by the obliquelines in FIG. 22A is adhered to thin plastic plate 157a whose surface ishard and therefore less likely to be damaged. And around the recordingmedium 157b, thin plastic plate 157c is framed. The material to beadhered to the recording medium per se and for the frame can be thesame. Because the surface of recording medium 157b can be set a bitlower than thin pate 157c for the frame, the light transmission layer150a can be protected from being damaged by the surface of carriage base189 when an optical card is introduced into the optical card reader.

FIG. 23B shows another method which is as effective as FIG. 23A. Thinplate 158a, which is cut out for the part for the recording layer and isof the same material as thin plastic plate 157a, is adhered to thesurface of optical card 150 shown in FIG. 22C.

Embodiment 17

Now, structure of the apparatus using these elements will be explained.The "card reader" of the present invention includes a magnetic cardreader and an optical card reader. A card reader 160 indicates both thecard readers, hereinafter. The "card" includes a magnetic card and anoptical card. A card 161 indicates both the cards. The card reader ofthe present invention appears like an interchangeable type hard diskdrive or a floppy disk drive. The card reader has features ofportability, dustproof, vibration and such in order to be used not onlyin a desk top type computer on desks but also in an apparatus usedoutdoors.

FIG. 24A and FIG. 24B show the card readers of the present invention.FIG. 24A shows a device having no door at the front panel 169. The cardreader 160 is composed of a frame part including a base 167 and a cover168, and a front panel 169. The front panel 169 includes a card inlet170, an eject button 171 and a display lamp 172. There are a powerconnector (not shown) for connecting a power source and an interfaceconnector (not shown) for connecting a controller at the back side ofthe apparatus.

FIG. 24B shows one embodiment of the front panel door of the cardreader. An overhung door 173 with a hinge (not shown) is on the frontpanel 169 and opens towards the arrow. The opening angle is 90 degreesor 180 degrees. If the opening angle is less than 90 degrees, the doorshuts by a spring (not shown) placed between the base 167 and theoverhung door 173. There is a hole 174 on the overhung door 173 forpassing a light from the display lamp 172. The hole 174 is filled withtransparent glass or plastic. It is possible to have a concave 175 atthe back side of the overhung door 173 when the eject button 171 comesout largely from the front panel 169.

Embodiment 18

A card detect mechanism for inserting/extracting card will now beexplained in detail.

FIGS. 25A, 25B, 25C, 25D and 25E show a motion of one embodiment of thecard detect mechanism. When the card 161 is inserted through the cardinlet 170 shown in FIG. 24A, the card detect mechanism detects the cardinsertion and generates a signal which initiates a following sequence ofoperations. One edge of a detecting element 176 is fixed to the upperpart of the front panel 169. The detecting element 176 is made of springmetal whose edge is crooked like a fishhook. Otherwise, the detectingelement 176 is made of broad and a thin spring metal panel whose edge iscrooked like a fishhook. The other edge of the detecting element 176contacts a sub-base 167a made of conductive material, such as iron oraluminum. The detecting element 176 and the sub-base 167a are connectedto a logic circuit 179 (2 input NOR gate in this embodiment) throughlead wires 177 and 178. The lead wire 177 is connected to a directcurrent power source of +5 volts through a pull-up resistance 180. Whenthe detecting element 176 contacts the sub-base 167a, the output of thelogic circuit is H (High) logically since voltage of the two inputs are0 volt (logically, L(Low)).

FIG. 25A shows a situation where the card 161 has not been insertedthrough the card inlet 170. The output of the logic circuit is Hlogically as stated above.

FIG. 25B shows a situation where the card 161 is inserted along thedirection of arrow. Since the detecting element 176 on the card 161 ismade of nonconductive material, the lead wire 177 becomes H and theoutput of the logic circuit 179 becomes L logically. FIG. 25C shows asituation where the card 161 has passed the detecting element 176.Namely, this situation is the same as the situation in FIG. 25A. Theoutput of the logic circuit 179 becomes H logically.

FIGS. 25D and 25E show situation of the card 161 being extracted towardthe arrow. The output of the logic circuits 179 become L and H. Thesituation of the card 161 being inserted or being extracted can bejudged from the output of the logic circuit 179. By using the abovestated method, it is possible to maintain the present situation of thecard, even when the card is not sustained by hand. Since the card 161inserted through the card inlet 170 is pushed onto the sub-base 167a bythe spring of the detecting element 176, it is possible to prevent thecard 161 from dropping even when the card 161 is inserted from up todown with the card reader 160 standing.

Embodiment 19

Another method of detecting the card insertion/extraction will now beexplained in this embodiment. The existence of the card 161 was detectedelectrically by using the detecting element 176 in FIGS. 25A to 25E. Itis also possible to detect optically. FIGS. 26A and 26B show oneembodiment of using an optical detector. In FIGS. 26A and 26B, there isa support spring 181 for pushing the card 161 onto the sub-base 167a.The support spring 181 is constructed similarly to the detecting element176 shown in FIGS. 25A to 25E. A light emitting element 182 and a lightreceiving element 183 are located close to the support spring 181.

FIG. 26A shows a situation where the card 161 is not inserted. There isnothing for blocking between the light emitting element 182 and thelight receiving element 183.

In FIG. 26B, a light from the light emitting element 182 is blocked bythe card 161. It is possible to convert two situations of FIGS. 26A and26B into electric signals and logic signals by using the light receivingelement 183 like FIGS. 25A to 25E. This method can be used when thesub-base 167a is made of nonmetal or the sub-base 167a is covered withnonconductive resin.

Embodiment 20

A mechanism for feeding and ejecting the card will now be explained.

FIGS. 27A, 27B and 27C show one embodiment of the card feeding mechanismfor feeding the card into the card reader. The card 161 is insertedthrough the card inlet by hand. When the card passes the card detectmechanism shown in FIGS. 25A to 25E and FIGS. 26A and 26B, a feedingmechanism 186 at the back of the card detect mechanism startspreparation corresponding with the card insertion.

A driving part of the feeding mechanism 186 of the present embodiment iscomposed of a driving roller 184 and a guide roller 185. The drivingroller 184 is made of hard material and the guide roller 185 is made ofsoft material. These two rollers are fixed to a base 167 (not shown). Itis possible to separate the two rollers from the feeding mechanism 186.The driving roller 184 is rotated by a direct current motor (not shown)or a stepping motor (not shown) fixed to the base 167 (not shown). Thedriving roller 184 and the guide roller 185 are interlocked with thelogic circuit 179 of the card detect mechanism shown in FIGS. 25A to 25Eand FIGS. 26A and 26B. When the card 161 is not inserted into the cardreader 160 and the output of the logic circuit 179 is H, the two rollersare halted. When the logic circuit 179 becomes L, rotation is startedand the driving roller 184 rotates towards the arrow. The guide roller185 contacts the driving roller 184. First, the card 161 is insertedthrough the card inlet 170 by hand. When the card 161 comes between thetwo rollers, the card is transmitted into the inside of the feedingmechanism 186 automatically.

When the card 161 comes into the inside of the feeding mechanism 186,the card 161 contacts a card side guide 187. The card side guide 187 isfixed to a carriage base 189 through a flat spring 188. The card sideguide 187 is for setting the card 161 in the carriage base 189 in thefeeding mechanism 186 accurately. There is a possibility of the card 161being distorted a little when the card is first led into the inside ofthe feeding mechanism 186 because of restraints of the driving roller184 and the guide roller 185. Therefore, the card side guide 187 doesnot give inappropriate power to the card 161 when the card 161 is fedinto the inside by two rollers. Then the card 161 is set along a lineX1-X2 by the card side guide 187 when the card 161 is away from the tworollers.

FIG. 27A shows the whole of the feeding mechanism 186.

FIG. 27B shows a situation of the card 161 being guided into the insideof the carriage base 189 by the two rollers in the direction of thearrow. Because of bending of the flat spring 188, the card 161 istransmitted into the inside of the feeding mechanism 186 appropriately.Even when the card 161 is guided in a distorted manner, the card 161 isguided into the inside of the feeding mechanism 186 smoothly because thecard side guide 187 moves a little in the direction of the arrow.

A card end guide 190 which is like the card side guide 187 is fixed bythe flat spring 191. The card end guide 190 can be pushed a little by apushing power of the card 161 guided into the inside. A optical sensor192 is fixed to the edge of the card end guide 190. The optical sensor192 generates a signal indicating card transmission finish when a lightis blocked by a part of the metal of the card end guide 190. After thedriving roller 184 rotates for a while, the roller is halted by thesignal. This is for removing the card 161 from the restraints of the tworollers. Then, the card side guide 187 pushes the side edge of the card161 by power of the flat spring 188 and the card 161 is set along theline X1-X2. The card end guide 190 sets the card 161 along a line Y1-Y2by power of a flat spring 191.

FIG. 27C shows a situation where the card 161 is inside the feedingmechanism 186 and the driving roller 184 is halted. The above stated isa sequence of operations for transmitting the card 161 into the feedingmechanism 186. The card 161 can be set along the X-axis which is basedon the carriage base 189. However, since the installing accuracy of thedriving roller 184 is not clear and a positional relation between edgesof the card 161 and the two rollers is not clear, the positioning alongY-axis is not accurate. It is needed to correct the positioningaccurately by using a track seek mechanism described later. If thecarriage base 189 is moved by the track seek mechanism in thissituation, the card 161 is extracted out of the carriage base 189 bypower of the flat spring 191. Therefore, it is necessary to push thecard 161 onto a base surface 189b of the carriage base 189 by a pressurepad mechanism described later. After the card 161 is pushed not togenerate a slippage, a movement operation of the carriage base 189 bythe track seek mechanism is started.

In FIG. 27A, a shape of an access opening 189a for the turntable on thecarriage base 189 is the same as an outline of a track locus of themagnetic card 18 shown in FIG. 12B or as a shape of the opticalrecording layer 150e of the optical card 150 shown in FIG. 22B. Theaccess opening 189a is shaped to have a space to not contact a turntable15, rotary transformer holder 20 and a turn table spacer ring 152 whenthe carriage base 189 moves.

When the magnetic heads 13a and 13b need to contact a surface of thecard 161, the magnetic heads 13a and 13b are projected out of the basesurface 189b of the carriage base 189. When the base surface 189b of thecarriage base 189 needs to be a standard plane of the magnetic heads 13aand 13b for reading/writing or to be a standard plane of the opticalcard 150 for reading/writing, the upper part of an edge 15h of theturntable 15, the upper part of an edge 20h of the rotary transformerholder 20 or the upper part of the turntable spacer ring 152 are made tobe lower than the base surface 189b of the carriage base 189.

A card support guide 187a made of plastic is fixed to a metal fitting ofthe card side guide 187 and a card support guide 187b made of plastic isfixed to a X-axis basic side of the carriage base 189. A space a littlelarger than the thickness of the card 161 is between the card supportguides 187a, 187b and the carriage base 189. The card support guides187a and 187b are to prevent the card 161 from slipping from thecarriage base 189 when the card is led in.

Embodiment 21

Another card feeding mechanism is explained in detail in thisembodiment.

FIG. 28 and FIGS. 29A and 29B show another embodiment of the feedingmechanism. In FIGS. 27A to 27C, the card 161 is led into the inside ofthe feeding mechanism 186 by two rollers. In this embodiment, the card161 is led into the inside of the feeding mechanism 186 by a broad belt193.

The broad belt 193 is installed between a belt driving roller 194 and anauxiliary roller 195 attached to the carriage base 189. Rotation of astepping motor and a direct current motor placed at the apparatus baseare conveyed to a gear 196 through a gear 197. The gear 196 fixed to arotation shaft of the belt driving roller 194 moves the belt 193. Inthis way, the card 161 can be led in and led out from the carriage base189. The card end guide 190, the flat spring 191 and the optical sensor192 are used in this method, as well as the cases in FIGS. 27A to 27C.The way of setting the card 161 along Y-axis in this embodiment is thesame as FIGS. 27A to 27C. However, it is difficult to correct thesetting of the card 161 along the X-axis since there is a restraint ofthe belt 193. Therefore, it is necessary to insert the card 161 throughthe card inlet 170 by hand in order to keep the card aligned along theX-axis accurately before the card 161 contacts the belt 193. FIG. 28shows a way of aligning the card along the X-axis. An X-axis referenceguide 198 on the sub-base 167a solves the above problem. A line a-b ofthe X-axis reference guide 198 is the base for the X-axis. Two flatsprings 199a and 199b are fixed to a side plate 200. The two flatsprings push the card 161 being transmitted to the line a-b of theX-axis reference guide 198.

Card support guides 187a and 187b made of plastic are set at the X-axisreference guide 198 and the side plate 200. There is a space a littlewider than the thickness of the card 161 between a base surface of thesub-base 167a and the card support guide 187a, 187b. This is to preventthe card 161 from coming off the sub-base 167a and the carriage base 189when the card 161 is led in. The line a-b of the X-axis reference guide198 on the sub-base 167a and the line X1-X2 on the carriage base 189 arealigned on the same line in this embodiment.

FIG. 29A shows a side view of the belt and the card. An advantage ofusing the belt 193 is that the card 161 is pressed uniformly from theabove when the card 161 is led in and out from the carriage base 189.This means that the belt 193 also has a role of a pad stated later.Speaking generally, an elastic material which can somewhat extend andcontract is preferred as the material of the belt. The material of thebelt should also have durability and much friction with the card 161. Ofcourse, the material of the belt driving roller 194 gives effect on thematerial of the belt. Depending upon the material of the belt, there isa possibility of a distortion being generated between the belt drivingroller 194 and the auxiliary roller 195. If the distortion is generated,a tension roller 202 shown in FIG. 29A should be installed. By pullingthe tension roller 202 in the direction of the arrow, the belt 193always has a specific tension.

FIG. 29B shows one embodiment of another method of using the belt. Anadvantage of this method is that dynamic range at right/left andfront/back of the belt 203 is small when the belt 203 rotates.Therefore, rotation of the belt driving roller 204 can be conveyedeffectively to the belt 203. There is an uneven rack portion 203a in themiddle of the belt 203. The rack portion 203a meshes with an unevennessof a gear portion 205 in the middle of the belt driving roller 204. Thediameter of the central part of the auxiliary roller 206 is smaller thanthe other not to contact the rack portion 203a of the belt 203.

It is also acceptable for the shape of the auxiliary roller 206 to havea gear shape portion like the gear 205 as the belt driving roller 204.It is also acceptable for not only having the rack portion 203a at onepart of the belt 203, but also having the rack portion 203a all over thebelt 203 and defining the whole part of the belt driving roller 204 andthe auxiliary roller 206 as the gear portion like the gear 205.

Embodiment 22

FIGS. 30A to 30E and FIGS. 31A and 31B show one embodiment of a pressurepad mechanism applied on the feeding mechanism. As the belts are used inthe feeding mechanism 186 in FIG. 28, the pressure pad mechanism is notnecessarily needed. However, in the feeding mechanism 186 in FIGS. 27Ato 27C, the pressure pad mechanism of the present invention is necessaryas well as the setting mechanism of the X-axis and the Y-axis of thecard 161.

FIGS. 30A to 30E show embodiments of the pressure pad 207. The materialof the pressure pad 207 in FIG. 30A has multiple small stings 207a onthe base 207b. The heads of the stings are fine and roots are thick, orthe shape of the stings are like a brush of same thickness. The stingsare made of elastic material, such as rubber or plastic. The heads ofthe stings are elastic enough to bend when the pressure pad 207 pushesthe card 161 from the upper side. The material of the pressure pad 207of FIG. 30B is made of styrene foam like a sponge. The pressure pad 207contracts when the pressure pad 207 pushes the card 161 from the upperside, and the pressure pad restores when the pressure on the card isremoved.

The material of the pressure pad 207 in FIG. 30C is the same material asthe belt 193 in FIG. 28. The material of the pressure pad 207 of FIG.30C contracts less than the cases of FIGS. 30A and 30B when the pressurepad is pushed. However, the material of the pressure pad 207 of FIG. 30Cgenerates a large friction against the movement of the card 161.

Regarding the material of the pressure pad 207 of FIG. 30D, the sidecontacting the card 161 is made of the same material as that of FIG.30C, and the other side is made of the material of FIG. 30B. Namely, thepressure pad 207 of FIG. 30D has each characteristic of FIG. 30B and30C.

In the case of FIG. 30E, the thin plate 154 of FIG. 21B is used as apart of the pressure pad 207. In the case of the magnetic card reader,the contact condition of the magnetic heads 13a, 13b with the magneticcard 1a is emphasized. In the case of the optical card reader, adistance accuracy between the optical card 150 and objective lenses ofthe optical head 151 is emphasized, because the objective lenses 151aand 151b of the optical head 151 are set away from the optical card 150and the optical card 150 is made of harder material than the magneticcard 1a. Accordingly, it is possible to have a structure of the pressurepad 207 wherein the elasticity with respect to up and down is reduced.In FIG. 30E, the thin plate 154 and a thin material 155 are used at theside contacting the optical card 150. A material 156 which is the sameas the elastic pressure pad 207 used in FIG. 30B is combined.

FIG. 31A shows a structure of a pad frame 208 for setting the pressurepad. The pressure pad 207 is set inside of the pad frame 208. (In thiscase, the material of FIG. 30D is used.)

FIG. 31B shows a situation where the pad frame 208 is fixed to thecarriage base 189. The pad frame 208 and the carriage base 189 areconnected by a hinge 209, and it can be opened and closed by a lever 212in the direction of the arrows. In the card reader 160 of the presentinvention, after leading the card 161 to the carriage base 189 of thefeeding mechanism 186 and pushing the card by the pressure pad 207, thecarriage base 189 is moved and information writing/reading operation isstarted as described later. Then, the carriage base 189 is returned tothe original position to extract the card 161 out of the apparatus andthe extracting operation is executed by moving the pressure pad 207.

In the present invention, the pad frame 208 is always down onto thecarriage base 189 except during the operations of leading the card inand out, for the purpose of minimizing the harmful influence of dustfrom the outside.

FIGS. 32A and 32B illustrate operation of the pad frame of the feedingmechanism. FIG. 32A shows a situation where data writing/readingoperation is ready to start with the card 161 in the feeding mechanism186. In FIG. 32A, the feeding mechanism 186 is moved away from thedriving roller 184 and the guide roller 185 placed at the apparatus baseby the track seek mechanism described later. FIG. 32B shows a situationwhere the driving shaft 211 is moved upwards, the lever 212 is liftedand the pad frame 208 is open, by sending direct current to terminals aand b of a solenoid 210. After the card is led in, the pad frame 208 canbe closed by the power of an extension spring 213 since upward power ofthe driving shaft 211 becomes zero by turning off the direct current ofthe terminals a and b of the solenoid 210.

FIG. 33A shows a detecting sensor for judging whether the card 161 isbetween the carriage base 189 and the pad frame 208 or not. A smallmicro switch 215 is fixed to the back side of the carriage base 189 inFIG. 33B. As shown in FIG. 33B, a detective end 215a protrudes slightlyfrom the carriage base 189. There is a through hole 217 in the pressurepad 207. When the card 161 is not inside, the detective end 215a of themicro switch 215 protrudes and its electrical output is off. As shown inFIG. 33C, when the card 161 is led in, the detective end 215a becomeshollow since the card 161 is pushed by the pressure pad 207 and itselectrical output turns on.

Embodiment 23

A track seek mechanism for moving the feeding mechanism 186 against thehead assembly of the card reader will now be explained in detail.

FIG. 34 shows one embodiment of the track seek mechanism of the cardreader. In the track seek mechanism, a plurality of linear guidebearings 218 are installed at the side of the carriage base 189 shown inFIGS. 27A to 27C. A needle 219a and a pre-load spring leaf 219b areinstalled at the other side of the carriage base 189. The linear guidebearings 218 assist front and rear seek operation of the feedingmechanism 186 through a guide rod 220. A stepping motor 221 is used as adriving power of the feeding mechanism 186 in this embodiment. Thestepping motor 221 includes two parts, a stator and a rotor. By sendingphase pulse current into plural coils in the stator, a rotating power isgenerated between the stator and the magnet in the rotor. Then, thestepping motor can rotate right and left as much as the anglecorresponding to value of pulse. As the rotor of this invention isunified with a lead screw 222, the rotation of the rotor is conveyed tothe lead screw 222. A needle 219a is buried diagonally in the spiralroot of the lead screw 222. A pre-load spring leaf 219b at opposite ofside of the lead screw 222 assists the mesh of the lead screw 222 andthe needle 219a. The basis of the track seek mechanism is to convert therotation of the lead screw 222 to a direct movement of the needle 219a.Accordingly, the right and left rotation of the stepping motor 221 makesthe feeding mechanism 186 move forwards and backwards.

Although a voice coil motor good for high speed is used in theconventional hard disk device to shorten access time, the voice coilmotor has a defect that it is easily shocked and consumes a lot ofelectricity.

The reason for using the stepping motor 221 in the embodiment of thetrack seek mechanism of the present invention is that the stepping motoris not easily shocked nor does it consume a lot of electricity. However,a moving speed of the stepping motor 221 is slower than that of thevoice coil motor. The stepping motor is appropriate for a recordingdevice in an apparatus driven by battery, such as a portable informationapparatus. It is possible to use the voice coil motor which is highspeed in this card reader 160 when it is not necessary to be portableand it is important to shorten the access time. A turntable with someheads (magnetic head or optical head) for writing/reading data on thecard 161 is rotated at high speed to make the access time shorter. Someobstacles caused by the above high speed rotation in the magnetic cardreader for example, can be removed by applying a float mechanism whichfloats a magnetic head 13a or 13b above the magnetic card 1a, because afriction and damage are not generated. Although the case of recording bycontact is explained in the above embodiments, the case of the magneticcard reader having the float mechanism can be also acceptable.

The pressure pad in the pad frame 208 shown in FIG. 34 is hollowedroundly. The height of the base surface of the carriage base 189(wherein the card 161 is led in) should be coincident with the linewhere the driving roller 184 contacts the guide roller 185 shown inFIGS. 27A to 27C. Besides, the line where the two rollers contact shouldbe close to the base edge of the carriage base 189. The round hollow iscurved largely for the pad frame 208 opening and closing.

Embodiment 24

Now, card positioning mechanism for positioning the card on the specificposition of the card reader accurately will be explained.

FIGS. 35A to 35C show how the card of the card reader of the presentinvention is set on the carriage base. FIG. 35A shows an assemblystructure of the pad frame 208 and the pressure pad 207. A opticalsensor 258 is inserted and fixed into a through hole 259 in the padframe 208 and the pressure pad 207.

The pad frame 208 is fixed to the carriage base 189. When the card 161is led in, the optical sensor 192 on the carriage base 189 shown in FIG.33A detects the card. In this case, the pad frame 208 comes down and thepressure pad 207 fixes the card. However, it is sometimes difficult toposition the card accurately because such an accuracy depends onaccuracies of the rotation of the driving roller 184, the positioning bythe card side guide 187 and the detection of the optical sensor 192. Inthis embodiment, an accurate positioning of the card is executed byusing the optical sensor 258. FIG. 35B shows a positioning mark 260having white areas and black areas printed on the card 161. The opticalsensor 258 detects this positioning mark 260 and determines the settingposition.

FIG. 35C shows signals detected when the optical sensor 258 detects thepositioning mark 260. The optical sensor 258 has two channels, namelyhas two pairs of reflection type sensors made of photodiode and opticaltransistor. Each output from each optical sensor is defined as S₁ or S₂.It is also defined that an output voltage of white area is V₁ and thatof black area is V₂. Outputs of S₁ and S₂ depending upon the detectedposition of the positioning mark 260 are shown in FIG. 35C. The mostappropriate point for positioning of each sensor is on the borderbetween the white area and black area of the positioning mark 260. Theborder lies on the point where the output voltage of S₁ or S₂ is V₁ /2plus V₂ /2. Accordingly, when the optical sensor 258 comes to A-B shownin FIG. 35C, the most appropriate position is set.

The card positioning mechanism of the card 161 of the present inventionuses the stepping motor 221 as an embodiment. Generally, the steppingmotor is mainly used in the positioning mechanism whose track density islow, for recording device such as floppy disk drive. Based on a servosignal recorded in a recording medium in advance for positioning, aservo control method is adopted. A highly accurate positioning operationis executed by controlling the phase current of the stepping motor 221based on the output voltages of S₁ and S₂ of the optical sensor 258 inthe present invention.

Now, the card holding mechanism, whose pad can be open, will beexplained.

FIG. 36 shows another embodiment of the feeding mechanism. A card holder399 is installed between the pressure pad 207 and the carriage base 189.The card holder 399 is for positioning the card 161 onto the carriagebase 189 accurately.

FIG. 37A shows the card holder 399. A flat portion 399a, shown shaded inthe figure, is for placing the card 161. The flat portion 399a is lowerthan a frame portion 399b and has a notch 399c. Positioning pins 400aand 400b are placed where the pressure pad 207 fixed to a cover 393adoes not cover the positioning pins 400a and 400b in assembling. In thecenter of the card holder 399, there is an access opening 189a for aturntable. There also is a through hole 401 for sensor part of the microswitch 215 (not shown) on the card holder 399. Cylindrical joints 402aand 402b for connecting with the carriage base 189 are installed at theside.

FIG. 37B shows the card 161 used in the present invention. The card 161has holes 405a and 405b for positioning, at the upper right and left.FIG. 37C shows a situation where the card 161 is in the card holder 399.The card 161 can be put in and taken out easily by using the notch 399c.

FIG. 37D shows a section in the situation where the cover 393a is pushedonto the card holder 399. This card holder 399 is fixed to the carriagebase 189 by the pressure pad 207. The joints 402a and 402b shown in FIG.37A are hinged through a cylindrical pole 404. The card holder 399 canopen around 45 degrees from the surface of the carriage base 189, withone or two torsion springs 406. Torsion springs 407a (not shown) and407b are fixed to the inside or the outside of the pad frame 208 and thecarriage base 189. The pad frame 208 and the carriage base 189 areusually closed together. The driving shaft 211 of the solenoid 210drives a lock release lever 395. The lock release lever 395 is placedinto a side slit 396 of the carriage base 189. A projection 408a at thetop of a latch 408, made of spring material and inside of the pad frame208, comes apart from the concave past (not shown) of the carriage base189. The pad frame 208 can be opened by lifting the cover 393a.

When the pad frame 208 is closed, the projection 408a of the latch 408meshes with the concave past of the carriage base 189. A direct currentmotor 22, a turntable 15, and a rotary transformer holder 20 under thecarriage base 189 are omitted in FIG. 36. Magnetic heads 13a and 13b inthe case of the magnetic card reader, and objective lenses 151a and 151bin the case of the optical card reader are also omitted. Regarding thestructure of the track seek mechanism, the stepping motor 221 and thelead screw 222 move the carriage base 189, on one side, which is thesame as FIG. 34. The lead screw 222 is between the needle 219a and thepre-load spring leaf 219b. The linear guide bearing 218 and the guiderod 220 are on the other side.

In FIGS. 32A and 32B, one side of the pad frame 208 and the carriagebase 189 is lost in order to feed the card 161 by the driving roller 184and the guide roller 185. The pressure pad 207 can be seen from theoutside. The method of feeding the card 161 in FIGS. 37A to 37D isdifferent from FIGS. 32A and 32B. In FIGS. 37A to 37D, the pad frame 208and the carriage base 189 have all the sides like a box and the box canbe opened. The features of having the micro switch 215 on the carriagebase 189 and the through hole 217 on the pressure pad 207 for detectingthe card 161 shown in FIGS. 33A to 33C are the same in FIGS. 37A to 37D.

Embodiment 25

In this embodiment, one example of a recording format of the track forreading and writing on the card will be explained. Each recording trackis composed of plural sectors.

FIGS. 1 to 37D explain the card readers 160 and the card 161 of thepresent invention. FIGS. 38A to 38C show one embodiment of the sectorformat. The card reader 160 has a plurality of two arc tracks on theconcentric circle which are symmetric in right and left. The card reader160 performs data reading and writing by one or two magnetic heads oroptical heads. Recording tracks 63a and 63b are divided into pluralsectors as shown in FIG. 38A. The format shown in FIG. 38B is applied ineach sector. This format is almost the same as the format used in floppydisk drive, optical disk drive and hard disk drive. However, the formatcan be different depending upon the system used.

In the case of the magnetic card of the present invention, the magneticcard reader can itself write preamble, sector synchronization, sectoraddress and preamble, frame synchronization, and data. In the case ofthe optical card, the preamble, sector synchronization and the sectoraddress should be stored in advance depending upon the medium and thenthe preamble, frame synchronization and data are written by the opticalcard reader.

In this invention, the sector pulse showing the original point of eachsector is not generated from data on the medium. An optical encoder 261is installed in a rotor 22b in the direct current motor 22 shown in FIG.38C. The optical encoder 261 is made of round paper or round plastic andhas slits. An optical sensor 261a of reflection type is installed in themagnetic circuit of a stator 22a. Slit data of the optical encoder 261is converted to a pulse signal by the optical sensor 261a. Thisconverted signal is used as the sector signal.

FIG. 39 shows the way of making an index signal from the sector signalin FIG. 38B. The (1) in FIG. 39 is a sector pulse signal stream. Whenthe pulse signal becomes low, a retrigger type one-shot circuit 262 isactivated. Supposing that a time constant of one-shot circuit 262 is atime width obtained by adding the time width between the sectors to thetime width of the sector pulse, the output of the retrigger typeone-shot circuit 262 can be shown as (2) in FIG. 39. The pulse in (3)shows the output of an AND circuit 263 of the signal in (1) and signalin (2). This pulse is called the index pulse and emerges at the head ofthe recording tracks 63a and 63b. The above sector pulse and the indexpulse are used for operation timing of the card reader 160 or are usedas a reference signal for writing/reading operation when sent to thecontroller (not shown) of the card reader.

Embodiment 26

The relation between the whole apparatus of the card reader afterassembling stated in the above embodiments and the card installationwill now be explained.

FIG. 40 shows the whole structure of the card reader of one embodimentof the present invention. The sequence of the card inserting andextracting, and the outline structure of the card reader 160 of thepresent invention without a cover 168 are explained as follows.

(i) Case of feeding the card into the card reader

First the overhung door 173 is opened and the card 161 (not shown) isinserted along the sub-base 167a, through the card inlet 170 of thefront panel 169. When the card 161 made of insulating material is ledin, the sub-base 167a is contacted by the card 161 and the detectingelement 176 in conduction becomes nonconductive. An inside controlcircuit of the card reader detects this situation. Then, the solenoid210 is moved to push up the lever 212 of the pad frame 208 and anopening for passing the card 161 is made between the carriage base 189and the pad frame 208.

Secondly, the direct current motor (not shown) or the stepping motor(not shown) is rotated. The driving roller 184 receives the aboverotation and rotates with the guide roller 185. Then, the card 161 isled into the inside of the carriage base 189. The card positioning alongthe X-axis and Y-axis is fixed at this time by the card side guide 187a,the card end guide 190 and the optical sensor 192 of the carriage base189 shown in FIG. 27. When the solenoid 210 turns off, the card 161 isheld between the carriage base 189 and the pressure pad 207 in the padframe 208.

The above operations are under control of the inside of the card reader160. After feeding the card is finished, a signal telling the finish issent to a controller outside of the card reader 160. These operationsare done until the card 161 is led into the inside of the card reader160.

(ii) Case of the card already being inside the card reader

If the power switch is turned on again after turning it off at the endof the data reading or data writing of the card 161, the card 161 isstill inside the card reader 160. In this case, the inside controllercircuit does not make the driving roller 184 and the solenoid 210 moveeven though the detecting element 176 indicates detection of a new card.The micro switch 215 shown in FIGS. 33B, 33C has already detected thecard 161 being installed.

(iii) Case of leading the card out

The card 161 can be led out of the card reader 160 when an eject button171 of the front panel 169 is pushed by hand or an order of cardejection is sent from the controller.

The solenoid 210 shown in FIG. 32A is operated based on the order ofcard ejection. The driving shaft 211 moves up and makes the pad frame208 open. As nothing restrains the card 161, the card 161 is pushedforward by power of the flat spring 191 at the back of the card endguide 190 on the carriage base 189. When the solenoid 210 operates, thedirect current motor (not shown) rotates and makes the driving roller184 and the guide roller 185 rotate. Since the card 161 is pushedforward by the card end guide 190, the card 161 is positioned betweenthe driving roller 184 and the guide roller 185. The card 161 is led outthrough the card inlet 170 by the two rollers.

Whether the card is led out or not is detected by the detecting element176 at the back of the card inlet 170. When the card 161 passes underthe detecting element 176, no electrical conduct can be made between thedetecting element 176 and the sub-base 167a. Then, rotation of thedriving roller 184 is stopped after rotating for a while. The speed ofleading the card out is set at slow in the present invention. The card161 is set to stop at a short distance from the driving roller 184 andthe guide roller 185 based on spring power of the detecting element 176even when the card reader 160 is positioned sideways. The nonconductivesituation lasts until the card 161 at the card inlet 170 is pulled out.

To start again, taking the card 161 out by hand, making the detectingelement 176 be in the original situation and inserting the card againthrough the card inlet 170 are necessary. The conductive andunconductive signals are used in circuits inside the card reader 160 andare sent to the controller.

Now, necessary structural elements in the card reader 160 which have notbeen explained will be described in reference to FIG. 40. An interfaceconnector 266 and a power connector 267 are installed in a back panel265, and they are connected with a circuit board 268 in FIG. 40.Circuits for writing/reading data, controlling the stepping motor,controlling the direct current motor, controlling the solenoid andcontrolling the inside, including output process of various sensors, arelocated on the circuit board 268.

A stopper 269 for stopping a wrong motion of the carriage base 189 bymisoperation is installed on an apparatus base 21. A micro switch 270next to the stopper 269 detects the wrong motion. A optical sensor 271for detecting home position is also installed on the apparatus base 21.The optical sensor 271 generates a signal when an optical shield plate272 at the side of the carriage base 189 passes. Leading the card 161 inand out of the apparatus is possible at the position where the abovesignal is generated.

The optical card reader of the present invention transfers the card intothe inside with the card holding mechanism when the card is put throughthe card inlet by hand. Then, the card is set at the specific positionto be prepared for writing and reading.

When extracting the card is directed, the card holding mechanismreleases the card and leads the card out through the card inlet.

Embodiment 27

Outlines of circuits for controlling the card reader and writing/readingdata are described as follows.

FIG. 41 shows a block diagram of circuits in the card reader. Aninternal controller 273 receives a track address, sector address, headnumber, clock signal, read/write command and recording data, from anexternal card reader control circuit 312 (not shown), through theinterface connector 266. The internal controller 273 sends a clocksignal for reproducing data and a signal for detecting error, to theexternal card reader control circuit 312. The internal controller 273sends encoded recording data generated inside, a read/write controlsignal and a head selection signal to a read/write circuit 274. Theinternal controller 273 receives an encoded data from the read/writecircuit 274 and decodes it into the original data. A direction signalfor the stepping motor 221 going forward or backward, and pulse numbersare sent to a stepping motor controller 275. An on/off signal for thedirect current motor 22 is sent to a DC motor controller 276. A rotationdirection signal and an on/off signal for the direct current motor 279are sent to a DC motor controller 277 for driving roller 184. An on/offsignal for the solenoid 210 is sent to a solenoid controller 278.Outputs from a micro switch 270, an optical sensor 228, a micro switch215, a photo sensor 258 and an optical sensor 192 are necessary signalsfor controlling the sequence in the internal controller 273. The microswitch 270 arranged inside the card reader is for detecting an overrun.The optical sensor 271 is for detecting a home position. The microswitch 215 is for detecting the card on the carriage base 189. Theoptical sensor 258 is for detecting a positioning mark of the card 161.The optical sensor 192 is for detecting a position of Y-axis of the card161 on the carriage base 189.

Embodiment 28

Features of the card 161 of the present invention will be described.

The card reader 160 of the present invention as well as a 3.5 inchfloppy disk drive, which is mainly used as a recording mediainterchangeable type of recording device, can be used as a file of acomputer and a word processor. The card reader 160 can be also used forthe recording medium of a card used in shopping, game, providinginformation, studying, understanding operation of a machine and so on.The information provided includes information on traffic, hotels,geographical and historical background of some place, news, books,companies, advertisements and so on.

(A) Card operation

The conventional prepaid card, such as a telephone card has a magneticrecording track along the long side of the magnetic card. Since accessof a specific direction along the long side of the card is onlyacceptable conventionally, it is necessary to insert the card in acorrect direction if the card has been inserted incorrectly into themagnetic card reader. However, the card 161 used in the card reader 160of the present invention can be acceptable independent of the directionof the long side with respect to front or rear as long as the card isinserted into the card reader 160 with data recording side below.Namely, data reproducing operation can be started even when the card isinserted oppositely with respect to front and rear.

The locus of the magnetic recording track has been explained in FIG.12B. The format of right and left arc recording track of the magneticrecording track is almost the same as a format for hard disk drive,floppy disk device and optical disk drive. Even when the magnetic card1a is inserted into the magnetic card reader oppositely, data on thetrack can be read accurately, since the rotation direction of arecording track 63 with respect to a magnetic head 13a or 13b is alwaysrelatively the same. The address alignment of the track and thedirection of the magnetic card 1a can be detected in the magnetic cardreader. In this case, the direction of the magnetic card 1a is knownfrom address information of the outermost tracks. The track detectingoperation responsive to a direction on the track address from theoutside controller is performed. By having data on the track address inthe magnetic card 1a converted oppositely with respect to front andrear, the track detecting operation can be performed. The trackdetecting operation can be performed without changing the direction ofthe magnetic card even when the magnetic card is inserted oppositely. Itis necessary to have another positioning mark 260 shown in FIG. 35B onthe card 161 for realizing the above.

When sector information including servo information is recorded in eachrecording track of recording medium in advance, positioning of the cardcan be performed without using the above positioning mark 260. Forexample, when servo information which extends to a neighboring track isput in a region of preamble, sector synchronization, sector addressinformation in a sector format as shown in FIG. 38B, positioning thecard can be performed without using the above positioning mark 260. Theabove servo information includes a servo pattern for sector servo usedfor a hard disk drive.

(B) Facility in data detection

As described in FIG. 12B, the recording tracks are aligned at regularintervals along the long side of the card 161. Forward and backwardaccess along the long side of the card 161 is needed to get contiguousdata. Sentences of a book are extended continuously, for example. Whenthe contents of the book are stored in one card, it is possible toreproduce data on the book from the card 161 sequentially by followingtracks one by one from the first track of the card 161 like a floppydisk drive or disk drive.

(C) Multiplexed magnetic recording method

Magnetic writing/reading methods using one or two magnetic heads havebeen explained in the above. Common features in the above methods are torecord data at surface of the magnetic recording medium and to write newdata over the old data. By writing the new data over the old data, theold data can be deleted and only the new data can be stored. As long asgap length and gap depth, material character of the magnetic core, corewidth and such of the magnetic head are the same in drives, such drivescan be compatible. This means that new data can be recorded in a trackof the magnetic card 1a where other data was already recorded in anotherdrive. What is described above is an essential condition for a drivewhose medium is interchangeable.

The card reader 160 and the card 161 of the present invention meet theabove condition. It is also acceptable to apply a multiplexed magneticrecording method for the purpose of multiplying functions and usages. Inmagnetic tape drives and such, the method of recording data at a deeplocation of the medium by magnetic head of long gap length and thenrecording data at the surface of the medium by magnetic head of shortgap length is used. Generally, it is difficult to delete data recordedby the magnetic head of long gap length, using the magnetic head ofshort gap length. In this case, if there is a big difference between thelong gap length and the short gap length, only a partial magneticcondition at the surface changes. The magnetic card where data recordedin advance by special recording drive for a deep location is used inthis invention. Otherwise, the method of making the gap length of one oftwo magnetic heads 13a and 13b long and making the gap length of theother of the two short is acceptable in the present invention.

There are two methods for reproducing data recorded in this manner. Whendata was recorded at the deep location in another drive and the gaplength of the magnetic head used in reproducing is short, one of theabove two methods is applied. The one of two methods is to produce dataat the deep location and the surface simultaneously and to separate thetwo signals by filter. As the frequency of data recorded at surface isgenerally defined to be more than ten times as high as data recorded atthe deep location, it is easy to separate them at the signal reproducingprocess. The other method is to reproduce data using two magnetic heads,one of which is the same as the magnetic head used in recording at thedeep location and the other of which is a magnetic head used for surfacerecording. Since the magnetic head whose gap length is long does nothave a good characteristic for high frequency, output signals read fromthe surface are small. Further, it is possible to reproduce datarecorded at the deep location by using a low-pass filter. On the otherhand, signals of low frequency recorded at the deep location can beremoved from the output of the magnetic head used for surface recording,by using a high-pass filter.

By using this procedure, it is possible to apply a method which is thesame as the servo method used in hard disc drive, for example. The servomethod is reproducing servo information recorded in the servo plane byservo head and positioning head based on the reproduced servoinformation. There is a method that a magnetic head having a long gaplength is used as one of the two magnetic heads 13a and 13b forreproducing servo information and a magnetic head having a short gaplength is used as the other of the two magnetic heads forwriting/reading data. There is another method of reproducing servoinformation and data simultaneously by two magnetic heads having shortgap length and separating the signals into two signal sources by asignal processing circuit. There is another method where one of the twomagnetic heads is exclusively used for writing/reading servo informationand the other magnetic head is used for writing/reading data. Namely, inthis case, the drive has a function of writing and reading the servoinformation itself.

Another method where speech and sound are recorded at the deep locationand data and image information which are rewritten frequently arerecorded at the surface can be applicable. The method of recordinginformation seldom rewritten at the deep location and informationfrequently rewritten at the surface can be also applicable.

(D) Combination with image information

A prepaid card in a market, such as a telephone card and a ticketmachine card, shows image information by color print or picture andnecessary information on issue, price and usage, on the surface of thecard. Such image information is useful for identifying kinds of cards.Regarding important information such as price information, amount isshown at the edge of the card and consumed price is recorded by punchingthe card and storing data on consumption in a stripe magnetic recordingmedium of the card back side.

On the top side of the commuter pass issued by Japan Railway, section,period, name and age of user are shown and on the back side of themagnetic recording medium, data on the above information is recorded incode.

The magnetic card and the optical card of the present invention as wellas the above prepaid card and commuter pass can show image informationfor identifying card kind and can show any number and any languagetogether. The most characteristic feature of the magnetic card and theoptical card of the present invention is that information shown on thetop side of the card and information recorded in the recording medium onthe back side of the card are indivisible. Namely, consistentinformation composed of the above information can be provided. Titles ofplural information recorded on the back side, chart, picture, positionof recorded information and important points of the contents are shownon the top side. Information recorded on the back side can be knownbased on the information shown on the top. The magnetic card and theoptical card of the present invention can be also used as a speechrecording/reproducing device through a card recorder.

Embodiment 29

The mechanism of reading/writing with the card holding mechanism fixedand with head rotating and moving sideways will now be explained.

FIG. 42 shows another embodiment of the card reader.

In FIG. 34, the carriage base 189 of the feeding mechanism 186 was movedby the stepping motor and the turntable 15 and the direct current motor22 are fixed to the apparatus base 21. On the other hand, the carriagebase 189 of the feeding mechanism 186 is fixed to the apparatus base 21,and the turntable 15, the direct current motor 22 and other attachmentsare moved in this embodiment. In FIG. 42, the stator 22a (not shown) ofthe direct current motor 22 is fixed to a head assembly mechanism 280.The rotor 22b (not shown) and the rotation shaft 16 move together. Theturntable 15 is attached to the rotation shaft 16 and the turntable 15rotates with the rotation shaft 16. A rotary transformer holder 20 isfixed on the head assembly mechanism 280.

The mechanism of movement of the head assembly mechanism 280 is the sameas that of the carriage base 189 in FIG. 34. A guide rod 220 penetratesthrough a linear guide bearing 218 at one edge of the head assemblymechanism 280. The guide rod 220 can move back and forth. A needle 219aand a pre-load spring leaf 219b are fixed to the other edge of the headassembly mechanism 280 firmly. A lead screw 222 is fixed to the rotationshaft of the stepping motor 221 and a needle 219a is fixed to root ofthe lead screw 222. There is the pre-load spring leaf 219b at theopposite side of the lead screw 222. Rotation of the lead screw 222 isconverted to a direct movement by the needle 219a.

A feature of this embodiment is that the head assembly including theturntable 15 and magnetic heads 13a and 13b rotates on the head assemblymechanism 280 within an access opening 189a for the turntable. Comparedwith the driving method of FIG. 34, the driving method in thisembodiment has an advantage that the depth of the drive can be shortersince it is not necessary to move the carriage base 189.

Embodiment 30

In the following, it will be explained how the thickness of the protectlayer, which is provided above the magnetic layer of the magnetic card,influences the reading performance of each of two kinds of heads; themagnetic head, e.g., the coil-type magnetic head 13a or 13b on theturntable 15 and the MR head (Magnetic Resistive head) shown in FIG.11B.

FIG. 43A shows the relationship between the coil-type magnetic head andthe reading track. In FIG. 43A, the information has been already writtenin the recording track 63 on the magnetic recording medium 62 and themagnetic flux Φ is always generated between magnetized S pole and Npole. By moving the magnetic recording medium 62 to the direction shownby the arrow F in the figure, a part of magnetic flux Φ flows from theedge of the head core 59 of the coil-type magnetic head, and themagnetic path is generated between the edge of the head core 59 and themagnetic recording medium 62. The magnetic flux Φ crossing the head coil61 changes as time passes, and the change is detected as the readingsignal by the terminals a and b. The reading performance of thecoil-type magnetic head is determined based on the magnetic material ofthe head core 59, the length of the magnetic path and the length or thewidth of the head gap. The greatest factor is the distance d between thehead core 59 and the magnetic recording medium 62, which determines theamount of the flow of the magnetic flux Φ from the magnetic recordingmedium 62.

FIG. 43A shows the MR head and the recording track. The magnetic flux Φgenerated from the recording track 63 crosses the MR element 501, andthe resistance corresponding to the amount of the magnetic flux Φ isgenerated between the terminals 501c and 501d. The difference betweenthe resistance value at that time and the resistance value of the casewhen the magnetic flux Φ is zero is used as the reading signal.

The MR element 501 is easily influenced by the outside magnetic field,not only by the magnetic recording medium 62. Accordingly, the MRelement 501 is usually covered with the thin magnetic shield film toeliminate the influence of the outside magnetic field except themagnetic flux Φ from the recording track 63 on the magnetic recordingmedium 62. Recently, a huge MR element which can obtain higher outputthan the conventional MR element has been in a practical use, in which athin metal film is inserted between the thin MR films of NiFe/Co,Co/NiFe to generate a small magnetic field.

FIG. 43C is an experimental result showing the relationship between thestandardized output of the coil-type magnetic head and the MR head,which are shown in FIG. 43A and 43B, and the distance d between the headand the magnetic recording medium. In the experiment, the standardizedoutput of the above two kinds of the magnetic heads are compared on thesame track on which the information has already written using the samemagnetic recording medium with the same distance d. The standardizedoutput of each head is noted while the distance d changes. The decliningratio is obtained by plotting the experimental result. Generally, if themedium is magnetized with an ideal sine-wave, the distance loss (dB) isobtained by the formula-K·d/λ where the distance is d, the recordingwave length is λ, and the loss constant is K. The loss constant K isdetermined based on the characteristics of the medium and the head. Asshown in FIG. 43C, the MR head has smaller loss constant K and isinfluenced by the distance d less than the above-mentioned coil-typemagnetic head. Therefore, the MR head is suitable for the magnetic cardwith a thin non-magnetic film overcoated on the surface of the magneticrecording medium. The magnetic card of the invention will be explainedin the following.

Generally, there are two kinds of magnetic cards; a magnetic cardwithout an overcoat on the surface of the magnetic recording medium anda magnetic card with a thin non-magnetic film overcoated on the surfaceof the magnetic recording medium. Two cases will be explained on usingthe coil-type magnetic head against these magnetic cards. In case of theformer magnetic card, the reading performance of the head is influencedonly by the roughness of the surface and the lubricating layer of themagnetic recording medium, and the distance d between the magneticrecording medium and the head can be almost ignored as well as the caseof the magnetic tape. The magnetic card of this kind can be used as arecording medium of huge capacity which has a high recording density anda good reading output. However, in the latter case, the thicker thenon-magnetic film becomes, the bigger the distance d is. The card thuscannot provide a high recording density and a good reading output aswell as a telephone card or a commuter pass of Japan Railway Co. whichare commonly used today. The use of the overcoated magnetic card is thuslimited.

When the MR head is used as a reading head, a high recording density andenough distance d can be provided, which is difficult to provide usingthe conventional coil-type magnetic head. In the experiment, a magneticrecording medium holding 1500 oersted is used. The experiment result wasgood enough for practical use with respect to SN ratio; 7500 frpi/100tpi when the distance d is 0.5 μm (including a slight roughness of thesurface of the magnetic recording medium), 2500 frpi/100 tpi when thedistance d is 1 μm. The above result is obtained by only one experiment.However, it is expected that the higher recording density could beobtained by further improvement of the magnetic recording medium and theMR head.

It is the main purpose of using MR head provided with the magnetic cardreader in the present invention to minimize the output loss caused bydistance d by the overcoat. While, the magnetic tape drive or the fixedmagnetic disk drive uses the MR head for a different purpose, that is,to provide a high bit density and a high track density for increasingthe recording capacity, since the MR head could be manufactured withthin film technology and is possible to manufacture finely andprecisely.

Embodiment 31

FIG. 44 is a sectional view of the magnetic card for using the MR headof the invention as a reading head. The conventional prepaid card, whichis commonly used, consists of protective layer, print layer, base(milk-white colored PET (polyethylene terephtalate)), magnetic recordinglayer, silver layer and print layer (layers are noted from the surfaceof the card). In the present invention, the overcoat of non-magneticfilm of the magnetic card corresponds the above silver layer. Theconventional silver layer has an overcoat of non-magnetic film more thansome μm thick, while the magnetic card 1a of the invention has anovercoat of non-magnetic film only less than 1 μm thick, which islubricant enough for long-time sliding of the head. In FIG. 44,protective layer 502, print layer 503, base (milk-white colored PET)504, magnetic recording layer 505, and protective layer 506 ofnon-magnetic film are layered in order. In the magnetic card 1a of theinvention, another print layer to cover the protective layer 506 couldbe provided. However it is not recommended because it expands thedistance d between the head and the magnetic recording layer 505. Ifanother print layer is needed, the area except the accessible area ofthe head can be used. For example, the area outside of the area 150b,150e and 150g, which are shown by oblique lined part of the optical cardin FIGS. 22A to 22C, can be used. Areas A and B of the magnetic cardwhich are shown in FIG. 13 can be used. As described above, the magneticcard of the invention can obtain two-digit larger recording capacitythan the conventional prepaid card by providing the MR head and theprotective layer 506 of less than 1 μm on the magnetic recording layer505.

Embodiment 32

The distance d between the head and the magnetic recording layer 505greatly influences both recording density and output, so that the headis better configured to directly contact the magnetic recording mediumas well as the magnetic tape to get a large recording capacity by onemagnetic card. However, the magnetic card can not be used practicallyfor a long time without an overcoat on the magnetic recording layer 505because it is easy to experience a failure caused by a flaw by carelesshandling or by sticking dust.

The present invention will provide a new method, by which the magneticrecording layer 505 directly contacts the head on writing/reading, andin the other cases, the surface of the magnetic layer 505 is protectedfrom flaw or dust. The method will be explained in detail referring tothe drawings.

FIGS. 45A to 45D show a principle of the magnetic card with a cover. Themagnetic card 1a has a protective cover 507 attached to the side AB. Thelength and the width of the protective 507 is equal to or less than thatof the magnetic card 1a. The protective cover can rotate 360 degrees.The card and the protective cover are combined with a thin sheet such ascellophane tape. On keeping or carrying the card, the protective cover507 covers the magnetic layer 505 of the magnetic card 1a as shown inFIG. 45A, so that the surface of the magnetic layer 505 is protectedfrom flaw and dust. When the magnetic card reader accesses the card, theprotective cover 507 is opened as shown in FIGS. 45B to 45C. The cover507 turns to the back of the magnetic card 1a as shown in FIG. 45D andthe magnetic recording layer 505 can be contacted by the head directly.After pulling the card out from the card reader, the protective covershould be turned back to the original place as shown in FIG. 45A.

Not illustrated in the figures, the present invention provides themagnetic card configured as follows:

(1) the protective cover 507 includes a protective layer and a printlayer;

(2) the protective cover 507 is made of elastic material and functionsas the pressure pad 207;

(3) a little adhesive material is put on a part of one side of theprotective cover 507 or the magnetic card 1a to keep the protectivecover from opening easily as shown in FIG. 45A. It is also possible thateither of the protective cover 507 or the magnetic card 1a has physicalshape to keep the protective cover opening easily;

(4) a card assembly including the magnetic card which has the magneticcard 1a and the protective cover 507 and the case, which is configuredas to receive the card and to show the front side surface of themagnetic card 1a and the back side of the surface of the protectivecover 507.

Embodiment 33

Another example of the magnetic reading circuit of Embodiment 8 will beexplained as Embodiment 33.

In the circuit shown in FIG. 10E, the primary coil 55a and the secondarycoil 55b of the new rotary transformer 48, the DC-AC converter 56 andthe AC-DC converter 57 generate plus DC voltage to drive the amplifier53a inserted between the magnetic head 13a or 13b and the secondary coil46b.

However, another method to supply electric power may be required becausethe noise from the oscillator, etc installed. inside of the DC-ACconverter 56 or the AC-DC converter 57 may appear on the path from themagnetic head 13a or 13b to the amplifier 53a and the primary coil 46aor the secondary coil 46b.

FIG. 46 shows a read/write circuit using a new method for electric powersupply. FIG. 47A shows a configuration using slip rings. In the figures,the same reference numerals are used for the same elements shown inFIGS. 10E and 7A. The following is described in relation to FIGS. 46 and47A.

Slip rings 508, 509 are cylindrical. An extended part of the rotationshaft 16 is inserted to the inside of the slip rings to fix them to therotation shaft. The slip rings 508, 509 are connected to the amplifier53a by the lead wire (not shown in FIG. 47A). Brushes 510, 511 are setas to contact each of the slip rings 508, 509 and are connected to theelectric power source and the ground with the lead wire (not shown inFIG. 47A). The contacting parts of the slip rings 508, 509, and thebrushes 510, 511 are made of conductive metal, e.g., an alloy of goldand silver, an alloy of silver and palladium or titanium nitride. Afastener 512 fastens the brushes 510 and 511 to the apparatus base 21.

In this configuration, when the turntable 15 rotates, the slip rings508, 509 turn and the brushes 510, 511 always contact the slip rings508, 509. Accordingly, direct current voltage flows to the amplifier 53afrom the electric source through the brushes 510, 511 and the slip rings508, 509. The slip rings 508, 509, the brushes 510 and 511 become moreabrasion-resistant by putting conductive grease on the contacting pointsof the slip rings 508, 509 and the brushes 510, 512, which also reducesthe load of the DC motor 22 for driving the turntable 15.

FIG. 47B shows another example using the slip rings according to theinvention. In this example, the slip rings 508, 509 and the brushes 510,511 and the fastener 512 are included inside of the apparatus. In FIG.47B, the same reference numerals are used for the same elements shown inFIG. 47A. The slip rings 508, 509 are cylindrical. The rotation shaft 16and the inside rib of the turntable 15 are inserted to the inside of theslip rings. The slip rings 508, 509 are fixed to the inside rib of theturntable 15. The brushes 510, 511 are set between the rotarytransformer 48 and the slip rings 508, 509 as to contact the slip rings508, 509. The brushes 510, 511 are set by the fastener 512 on theapparatus base 21. In this configuration, the apparatus becomes thinnerthan the above embodiment. The slip rings 508, 509 and the brushes 510,511 are prevented from sticking dust, which enables stable supply of theDC voltage.

The above supplying method of direct current voltage is provided fordriving the amplifier 53a in the secondary coil 46b. The method can beapplied to supplying DC bias between the terminals c and d of the MRelement 501 shown in FIG. 43B. The method can be also applied tosupplying DC voltage of the MR element 501 and transferring the readingsignal. If a coil-type DC magnetic eraser head which erases the recordon the magnetic card is provided, the above method can be applied byconnecting the coil-type DC magnetic eraser head to the slip rings. Inthis embodiment, two sets of the slip rings 508, 509 and the brushes510, 511 are used for the electric source and the ground. When anamplifier which requires plus and minus electric sources is used, threesets of the slip rings and brushes can be used.

However, in the configuration as shown in FIG. 47B, the more the numberof the slip rings 508, 509 and the brushes 510, 511 increases, thethicker the apparatus becomes. To solve the above problem, anotherexample of the configuration will be explained. FIG. 47C is a sectionalview of a card reader as another example according to the embodiment. InFIG. 47C, the same reference numerals are used for the same elementsshown in FIG. 47A. In this example, three sets of the slip rings and thebrushes are used in the apparatus. The inside diameter of the slip ring509 is expanded to include the slip ring 513 inside of the slip ring509. The slip rings 509, 513 are fixed to the slip ring 508 and the slipring 508 is fixed to the inside rib of the turntable 15. The brushes510, 511 are set between the rotary transformer and the slip rings 508,509 by the fastener 512 on the apparatus base 21 to contact the sliprings 508, 509 as well as the above embodiment. The brush 514 is setbetween the slip ring 513 and the inside rib of the turntable 15 by thefastener 515 on the apparatus base 21 to contact the slip ring 513. Inthe above configuration, three sets of the slip rings and brushes can beused in the apparatus, though the apparatus is as thick as the exampleshown in FIG. 47B.

Another slip ring and brush can be used as follows (not illustrated inthe figure); a new additional brush can be set between the fastener 515shown in FIG. 47C and the rotation shaft 16 and a new slip ring can befixed to the inside rib of the turntable 15.

Embodiment 34

Another embodiment will be described using the primary coil and thesecondary coil of the rotary transformer. In the configuration as shownin FIG. 10D, when the coil ratio of the primary coil 46a and thesecondary coil 46b is set as 2:1, the primary coil 46a can get twice asmuch voltage of the reading signal as the voltage of the reading signalof the secondary coil 46b.

In the configuration as shown in FIG. 10D, the coil ratio of the primarycoil 46a and the secondary coil 46b is set as 2:1. When the number ofcoils of the primary coil 46a is large, the transition period of currenton changing the recording signal in the primary coil 46a becomes longbecause of the increase of the inductance of the primary coil 46a.Therefore, it is difficult to reproduce high frequency recording signalsthrough the magnetic head 13a or 13b. When the coil ratio of the primarycoil 46a and the secondary coil 46b is set as 2:1 and the number ofcoils of the secondary coil 46b is small, the inductance of thesecondary coil is decreased. The inductance of the magnetic head 13a or13b should be set smaller to match the impedance. Accordingly, thenumber of coils of the magnetic head 13a or 13b should be small, whichdecreases the voltage of the reading signal. Thus, the voltage of thereading signal input to the write/read circuit 53 cannot be increased incase where the coil ratio is set 2:1 compared with the case where thecoil ratio of the primary coil 46a and the secondary soil 46b is set1:1.

This embodiment is provided to solve the above mentioned problem and isexplained in relation to the figures. FIG. 48 shows a configuration of awrite/read circuit of the embodiment. In FIG. 48, the same referencenumerals are used for the same elements shown in FIG. 10D. A center tap516 is provided with the center part of the primary coil 46a and isconnected with the write/read circuit 53. The winding number n1 of coilsbetween the center tap 516 and one of the terminals of the primary coil46a equals the winding number n2 of coils between the center tap 516 andthe other terminal of the primary coil 46a. In this configuration, onwriting the information, the writing electric current flows from thecenter tap 516 to one or the other of the terminals of the primary coil46a as to transmit to the secondary coil 46b. On reading theinformation, the reading electric current does not flow through thecenter tap 516, but the reading signal is transmitted from the secondarycoil 46b to the primary coil 46a.

The case in which the winding number n3 of the coils of the secondarycoil 46b is set as n1=n2=n3 is compared with the case in which thewinding number of the primary coil equals to the winding number n3 ofthe secondary coil 46b and the center tap is not used as shown in FIG.10D. On writing the information, the writing electric current flows fromthe center tap 516 to one or the other of the terminals of the primarycoil 46a as to transmit the writing signal to the secondary coil 46b.The transition period of the electric current on switching to thewriting electric current is the same as the case shown in FIG. 10D. Thewriting signal is transmitted in the rotary transformer in the same wayas the case shown in FIG. 10D. On reading the information, the readingsignal from the secondary coil 46b is transmitted to the primary coil46a without using the center tap 516, so that the coil ratio of theprimary coil 46a and the secondary coil 46b becomes 2:1. This enablesthe reading signal transmitted to the write/read circuit 53 to increaseits voltage to twice as high as the case shown in FIG. 10D.

As described above, by providing the center tap with the primary coil,the reading signal from the head can be transmitted without anyinfluence to the writing electric current. This method can be applied tothe case in which the distance from the primary coil of the rotarytransformer to the write/read circuit 53 is long, in order to improvethe SN ratio which is influenced by the increased outside noise causedby the long distance.

Embodiment 35

The following is an adjusting mechanism of the magnetic head on theturntable according to the invention.

The conventional magnetic card has only low recording density and thecard reader has a single magnetic head. The written information on themagnetic card can be read even if the head gap is not well positioned inthe apparatus.

In order to get a large recording capacity of the card, the recordingdensity should be higher and a plurality of magnetic heads are needed inthe card reader. When the magnetic head is positioned without adjusting,the head gap may be incorrectly positioned, which causes the apparatusto be uninterchangeable with others. In this embodiment, the headadjusting mechanism enables the apparatus to be interchangeable.

An adjusting mechanism of the magnetic head will be explained in thefollowing. The same reference numerals are used for the same elements inthe previously mentioned mechanism. FIG. 49 shows a plan view of themagnetic head adjusting mechanism according to the invention. FIG. 50shows a sectional view of the magnetic head adjusting mechanism of theinvention with a microscope provided. FIG. 51 shows a sectional view ofthe adjusting mechanism for adjusting a pitching direction. The pitchingdirection is a rotation direction having the radius direction of theturntable as the rotation axis. FIG. 52 shows a sectional view of theadjusting mechanism for adjusting a rolling direction. The rollingdirection is a rotation direction having the sliding direction of themagnetic head as the rotation axis. FIG. 53 shows an interference stripewhich appears when the contacting part of the slider of the magnetichead contacts a glass plate. FIG. 54 shows a plan view of the magnetichead adjusting mechanism for adjusting the head position.

In FIG. 49, a head holder 517 holds the magnetic head 13a positioned andfixed by an adhesive or the like. A head holder 518 holds the magnetichead 13b set in the opposite side of the head holder 517. Screw holes517a, 517b, 517c, and 517d are not aligned and provided with the headholder 517. Screw holes 518a, 518b, 518c, and 518d are provided with thehead holder 518. Screw holes 517e, 517f are dimensioned for fasteningscrews 519a, 519b and the diameters of the holes 517e, 517f are a littlegreater than the diameters of the screws 519a, 519b. 519c, 519d, 519e,and 519f also denote fastening screws. 520a, 520b, 520c, 520d, 520e,520f, 520g, and 520h denote adjusting screws. 521 denotes a U shapedpart. 521a denotes an extended part of the U shaped part 521, 521bdenotes a right hand part of the U shaped part 521, and 521c denotes aleft hand part of the U shaped part 521. 522a, 522b, 522c, and 522d areadjusting screws. A flat spring 523 biases the head holder 517 to thedirection shown by an arrow A. 523a denotes an L shaped hand part of theflat spring 523. A projected engaging part 523b contacts a side 517g ofthe head holder 517. The flat spring 523 is fixed by screws 524a, 524b.

In FIG. 50, 525 denotes a glass plate, 525a denotes a back of the glassplate, 525b denotes a face of the glass plate, and 526 denotes a glassplate holder. A standard plane 526a is provided with the glass plateholder 526 to be the standard of the height of the magnetic heads 13a,13b. 527 denotes a microscope, 528 denotes a microscope holder, 529denotes a bearing, and 530 denotes a weight.

A head positioning method using the magnetic head adjusting mechanism ofthe invention will be explained in the following. As shown in FIG. 50,the shaft 16 projected from the turntable 15 penetrates through thebearing 529 fixed to the glass plate holder 526 to enable the turntable15 to rotate. The glass plate 525 is set on the standard plane 526a,which defines the height of the magnetic heads 13a, 13b, of the glassplate holder 526. The weight 530 is set on the face 525b of the glassplate 525 to fasten the glass plate 525. In another approach, the glassplate can be fastened by a screw, etc. The microscope holder 528 forholding the microscope 527 for observing is set on the glass plateholder 526. The microscope holder 528 should be set in the place wherethe contacting part 25a of the slider 23 of the magnetic head 13a can beobserved by the microscope 527. FIG. 53 shows interference stripes whichappear when the contacting part of the slider of the magnetic headcontacts the glass plate. Primary interference stripe 531a and secondaryinterference stripe 531b appear in a small clearance between thecontacting part 25a of the slider 23 of the magnetic head 13a and theback 525a of the glass plate. The position of the magnetic head shouldbe adjusted with observing these interference stripes.

The head holder 517 holding the magnetic head 13a is provided with theturntable 15 as shown in FIG. 49. The fastening screws 519a, 519bpenetrate the two screw holes 517e, 517f provided with the head holder517. The fastening screws 519a, 519b are fastened temporally to theturntable 15 so that the head holder 517 can move a small distancevertically against the turntable but cannot be removed from theturntable. The adjusting screws 520a, 520b, 520c and 520d aredimensioned for the four screw holes 517a, 517b, 517c and 517d providedwith the head holder 517, and the four adjusting screws 520a, etc. arefastened so that the four tips of the adjusting screws contact thesurface of the turntable 15.

The U shaped part 521 is fixed to the turntable 15 by the fasteningscrews 519e, 519f. The adjusting screw 522a penetrates through the righthand part 521b of the U shaped part 521 from the direction shown by thearrow B to contact the right wing side 517j of the head holder 517. Inthe same way, the adjusting screws 522b, 522c provided with the extendedpart 521a of the U shaped part 521 are fastened to contact the wingsides 517h in the direction shown by the arrow C. The adjusting screw522d is fastened to contact the left wing side 517i of the head holder517 in the direction shown by the arrow D.

The projected engaging part 523b provided with the L shaped hand part523a of the flat spring 523 contacts the side 517g of the head holder517, and biases the head holder 517 to the direction shown by the arrowA to give the preload to the head holder 517. The projected engagingpart 523b is set between the adjusting screws 522b and 522c, and theflat spring 523 is fixed to the turntable 15 with the screws 524a, 524b.

An adjusting method for the magnetic head position will be explained inthe following. The magnetic head 13a is shown FIGS. 49 and 50. When theglass plate 525 is set at the standard plane 526a, the back 525a of theglass plate 525 becomes the standard for adjusting the magnetic head13a.

For example, each tip of the four adjusting screws 520a, 520b, 520c, and520d is contacts the surface of the turntable 15, and the head holder517 is fastened to have some space vertically. To adjust the position ofthe magnetic head 13a, the four adjusting screws 520a, 520b, 520c, and520d should be tightened. When the adjusting screws 520a, etc. aretightened, the head holder 517 rises making the vertical space. The headholder 517 can be inclined by changing how much each of the fouradjusting screws 520a, etc is tightened. Thus, the position of themagnetic head 13a held by the head holder 517 can be adjusted.

On adjusting the magnetic head 13a in the pitching direction, the headholder 517 is inclined to the direction shown by the arrow E bytightening the adjusting screw 520d more than the screw 520c as shown inFIG. 51. On adjusting the magnetic head 13a in the rolling direction,the head holder 517 is inclined to the direction shown by the arrow F bytightening the adjusting screw 520d more than the screw 520a as shown inFIG. 52.

The four adjusting screws 520a, 520b, 520c, and 520d are tightened thesame for adjusting the height of the magnetic head 13a itself.

After adjusting the magnetic head 13a in the above way, the head holder517 is fastened temporally by the fastening screws 519a, 519b. The glassplate 525 is set on the standard plane 526a of the glass plate holder526 so that the contacting part 25a of the slider 23 of the magnetichead 13a can be observed by the microscope 527.

On observing by the microscope, the position should be adjusted so thatthe interference stripe can be seen in a small clearance between thecontacting part 25a of the slider 23 of the magnetic head 13a and theback 525a of the glass plate 525 as shown in FIG. 53. Until both of theprimary interference stripe 531a and the secondary interference 531b canbe seen simultaneously, the contacting part 25a of the slider 23 of themagnetic head 13a should be adjusted a plurality of times to contact theback 525a of the glass plate 525 with a proper position.

After adjusting one of the magnetic heads, the magnetic head 13a, inheight direction, rolling direction, and pitching direction, the headholder 517 is fastened by the fastening screws 519a, 519b. Then, theturntable 15 is rotated around the rotation shaft 16, and the magnetichead 13b held by the other head holder 518 is set to be observed by themicroscope 527. The position of the magnetic head 13b is thus adjustedin the same way as the magnetic head 13a.

The position of the head gap 24 is adjusted after adjusting the positionof the head. In this embodiment, the head on the flat double-barrelslider, which is shown in FIG. 4A, is used. First, the center of theturntable 15 is detected. The microscope 527 is positioned so that thecrossing line 527b of the lens 527a of the microscope 527 is on theradius line 532 through the center of the turntable 15 as shown in FIG.53. The microscope 527 is also positioned so that the crossing point527d matches the predetermined radius from the center of the turntable15. To adjust the position of the head gap, the magnetic head is movedso that the crossing line 527b matches the edge plate 24a of the headgap 24, and the crossing line 527c, which crosses the crossing line527b, also matches the edge part 24b of the head gap 24. The aboveprocedure will be explained in detail in the following.

The head holder 517 can be moved in the direction of B within the spacebetween the hole 517c and the screw 519a, and the hole 517f and thescrew 519b by tightening the adjusting screw 522a provided with theright hand part 521b of the U shaped part 521 and by loosening theadjusting screw 522d provided with the left hand part 521c as shown inFIG. 49. By tightening and loosening the screws 522a, 522d in theopposite direction, the head holder 517 can be moved in the direction ofD. By tightening the adjusting screws 522b, 522c provided with theextended part 521a the same amount, the head holder 517 is moved in thedirection of C against the flat spring 523 for biasing the head holder517, and the holder 517 is moved in the radius direction to the centerof the turntable 15. When the adjusting screw 522c is tightened morethan the adjusting screw 522b, the head holder 517 is turned to thedirection G as shown in FIG. 54 because a moment toward direction Ggenerated with the projected engaging part 523b of the flat spring 523works as a pivot.

As described above, the position of the head gap can be moved in theplane. The flat spring 523 always gives preload to the head holder 517in the direction of A, so that the head holder 517 can be moved a smalldistance without any backlash.

When the height, the inclination, and the position of the head gap ofthe two magnetic heads have been adjusted, the adjusting screws 519a,519b, 519c, and 519d are tightened to lock. The flat spring 523 forbiasing and the U shaped part 521 are removed, and then the wholeprocedure of adjusting the magnetic head has been finished by removingthe turntable 15 from the bearing 529.

Embodiment 36

Another magnetic head adjusting mechanism will be explained in thefollowing. The mechanism includes a sphere provided under the headholder.

A sphere 533 is provided to contact the head holder within the space foradjusting by the adjusting screws 520a, 520b, 520c, and 520d foradjusting the head in the rolling direction as shown in FIG. 55. Thehead holder 517 is mounted on the sphere and the position of the head isadjusted in the same way as the case shown in FIG. 54. On adjusting themagnetic head 13a, each of the four adjusting screws 520a, 520b, 520c,and 520d is tightened from the upper side of the head holder 517. Foradjusting the head in the rolling direction, the adjusting screw 520d istightened more than the screw 520a. The head holder 517 is inclined byturning around the contacting part 533a of the sphere 533.

For adjusting the head in the pitching direction, the head holder 517can be inclined by turning around the contacting part 533a of the sphere533 in the same way as adjusting in the rolling direction. When theheight of the contacting part 533a of the sphere 533 is adjustedpreviously, the magnetic head 13a does not need to be adjusted in theheight direction. The head can be adjusted using only three adjustingscrews as follows: The adjusting screws 520i, 520j, and 520h are placedas shown in FIG. 56, and the sphere 533 is placed among the screws. Thehead can be adjusted in the same way as the configuration using fouradjusting screws as shown in FIG. 49.

Embodiment 37

Another head adjusting mechanism using a head holder carriage will bedescribed referring to FIGS. 57 and 58.

The position of the head of the head holder 517 is adjusted on a headholder carriage 534 provided under the head holder 517. The head holdercarriage 534 can be positioned on the turntable by tightening the fouradjusting screws 522a, etc.

The position of the head is adjusted by tightening the four adjustingscrews 520a, etc. with contacting the head holder 534, then the headholder 517 is fastened to the head holder carriage 534 by the fasteningscrews 519g, 519h. Then, the position of the head gap is adjusted. Wingparts 534a, 534b of the head holder carriage 534 are pressured bytightening each of the adjusting screws 522a, 522b, 522c and 522d.

Embodiment 38

In the above embodiment, the head adjusting mechanism has been explainedfor the head mounted on the flat double-barrel slider 23a. As shown inFIG. 59, the position of the head mounted on the button slider 23b canbe also adjusted by observing the interference stripe, and the head gapcan be adjusted in the same way as Embodiment 35.

Embodiment 39

A contact mechanism of the magnetic head and the magnetic card will beexplained in this embodiment.

The magnetic head and the card holding mechanism according to theinvention will be explained in relation to FIG. 60. In FIG. 60, magnetichead holders 535a, 535b are fastened on the turntable 15 by the screws,etc. The magnetic heads 13a, 13b are fixed on the magnetic head holders535a, 535b. As described in Embodiment 38, the button-type magneticheads 13a, 13b have a spherical contacting part or a projected engagingpart as the contacting part, which includes the head gap (not shown inthe figure). This has been explained in Embodiment 38.

A pressure pad 207, which faces the magnetic card and presses the cardto the magnetic heads 13a, 13b, is fixed on a pad frame 208. The side ofthe pressure pad 207 faced to the magnetic head is adjusted by the padframe 208 to be almost vertical with the rotation shaft of the turntable15. In the card reader, the scanning locus of the rotation of themagnetic head should match the information track on the card. Therefore,the card 1a, the pressure pad 207, and the pad frame 208 are stationaryrelatively except at the inserting or removing time of the card 1a. Forexample, when the card 1a is carried in the direction of the long sidefor changing the information tracks on the card, the pressure pad 207and the pad frame 208 are also moved with the card 1a in the samedirection. The pressure pad 207 is made of porous polymeric materialssuch as sponge, or textile materials such as furfelt, the rigidity ofwhich is far lower than the magnetic card 1a.

The following is contacting operation with the magnetic card.

In this embodiment, the magnetic card 1a contacts the magnetic heads13a, 13b locally by being pressed by the pressure pad 207 forming theplane of the rotation as a standard plane which includes the tips of themagnetic heads 13a, 13b. The magnetic card 1a contacts the tips of themagnetic heads 13a, 13b, which have a spherical or projected surface, bybeing pressed by the pressure pad 207 and by pressure force from themagnetic heads 13a, 13b. The vertical displacement of the tips of themagnetic heads 13a, 13b is absorbed by the elasticity of the pressurepad 207. The vertical position of each tip of the magnetic heads 13a,13b is kept almost the same during the operation.

The tips of a plurality of the magnetic heads 13a, 13b are set on theplane vertical with the rotation shaft of the turntable 15, and eachhead gap is placed on the top of the chips. The pressure pad 207 is seton the plane, which is parallel with the vertical plane of the rotationshaft of the turntable 15. Therefore, when the magnetic card 1a ispressed enough for contacting the magnetic head 13 by the pressure pad207, the head gap always contacts the magnetic card 1a.

On using a gimbal spring, which is commonly used for a floppy disk driveor a hard disk drive, the magnetic heads 13a, 13b are likely to inclinebecause of the centrifugal force of the magnetic heads 13a, 13b given bythe rotation of the turntable. In this case, the position of themagnetic heads 13a, 13b is difficult to adjust. In the configurationaccording to this embodiment, the magnetic heads 13a, 13b are difficultto incline even if the magnetic heads are given centrifugal force. Theposition of the magnetic heads 13a, 13b can be adjusted easily becausethe turntable 15 is set stationary. Even if the turntable 15 rotates,the geometrical position of the magnetic heads and the turntable keepsthe same positional relation as in the stationary condition. Thus, themagnetic card 1a always contacts the magnetic heads 13a, 13b, whichenables the card reader to have a good write/read performance.

Embodiment 40

Another improved configuration, in which the magnetic card contacts themagnetic head better, will be explained as another embodiment.

FIG. 61 shows the magnetic heads and the card holding mechanismaccording to the invention. In FIG. 61, flat springs 536a, 536b have thesame shape. A spacer 537a the magnetic head side and a spacer 537b onthe fixing part side are placed with a predetermined interval. The flatsprings 536a, 536b are fixed on the top sides and the bottom sides ofthe two spacers 537a, 537b. The magnetic heads 13a, 13b are fastened onthe edge of the flat spring 536a, to which the spacer 537a on themagnetic head side is fixed. The bottom of the flat spring 536b, towhich the spacer 537b on the fixing part side is fixed, is fastened by aspacer 538. The spacer 538 forms a space between the bottom of the flatspring 536b and the turntable 15 so that the flat springs 536a, 536b canchange form vertically.

The magnetic heads 13a, 13b have spherical or projected contacting partsfor contacting the magnetic card 1a as in Embodiment 39, each of whichincludes the head gap. When a plurality of the magnetic heads aremounted, the bottom of the flat spring 536b, to which the spacer 537b onthe fixing part side is fixed, can be adjusted by tightening theadjusting screws (not shown) as in Embodiment 39. However, in thisembodiment, the flat springs 536a, 536b which mount the magnetic heads13a, 13b can move up and down, so that the position of the head can beadjusted within the desired accuracy. Namely, each tip of the magneticheads is not required to be in the same plane, which is different fromEmbodiment 39. The apparatus of the embodiment is characterized asfollows:

1) each tip of the magnetic heads is placed on a vertical plane with therotation shaft of the turntable 15, but is not required to be in thesame plane;

2) each head gap is placed on the top of the tip;

3) the center line of the locus of each magnetic head (that is, thecenter of the track width) is on the same circle; and

4) the azimuth angle of each magnetic head can be adjusted to be thesame.

A support pad 539, which is fixed to the pad frame 208 (not shown in thefigure), faces and supports the magnetic card 1a when the magnetic heads13a, 13b are pressed by the flat springs 536a, 536b with predeterminedpressure force. In this configuration as in Embodiment 39, the relativepositions of the magnetic card 1a and the support pad 539 are keptstationary during the operation except at the feeding time and theejecting time of the magnetic card. In another configuration, in whichthe pad frame 208 serves as the support pad 539, the same effect can beobtained. Far higher rigidity is required for the support pad than themagnetic card 1a or the flat springs 536a, 536b. The contacting planewith the magnetic card 1a is set almost parallel with the vertical planeof the rotation shaft of the turntable 15. However, when dust, etc.sticks to the magnetic card 1a and comes between the magnetic card 1aand the support pad, the shape of dust is easily printed on the cardsurface because of the high rigidity of the support pad 539. Themagnetic heads 13a, 13b thus do not contact the magnetic card 1a well,which reduces write/read performance. Therefore, the support pad 539should be made of conductive materials, which prevents electrostaticadsorption of dust, or Teflon coated materials, which do not easilyadsorb dust.

The magnetic card 1a is locally placed in contact with the support pad539 by pressing the magnetic heads 13a, 13b with the flat springs 536a,536b using the support pad 539 as the standard plane. As a differentaspect from Embodiment 39, the magnetic heads 13a, 13b are moved tofollow the surface of the magnetic card 1a. The magnetic card 1a ispressed to the support pad 539 by the contact pressure from the magneticheads 13a, 13b caused by the flat springs 536a, 536b, and the magneticcard 1a is held between the magnetic heads 13a, 13b and the support pad539. Each of the tips of the magnetic heads 13a, 13b having spherical orprojected contacting parts are located at the center of the contactingarea where the pressure force is generated. The two parallel flatsprings 536a, 536b make the magnetic heads 13a, 13b move only verticallywith the support pad 539. The vertical displacement of the magneticheads 13a, 13b can be absorbed by the flat springs. The magnetic heads13a, 13b do not incline, so that the positions of the tips of themagnetic heads 13a, 13b do not change.

As described above, each tip of the magnetic heads 13a, 13b is placed onthe vertical plane with the rotation shaft of the turntable 15, and eachhead gap is placed on the top. The support pad 539 is placed in almostparallel with the vertical plane with the rotation shaft of theturntable 15. When the magnetic card 1a is pressed into contact thesupport pad 539, the head gap always contacts the magnetic card 1a.

The magnetic heads 13a, 13b are moved only vertically with the turntable15 because of the two parallel flat springs 536a, 536b. When a pluralityof magnetic heads are used, only pressure force needs to be changed,even if each of the magnetic heads has vertical displacement. If thegeometrical relationship of the turntable 15, the magnetic heads 13a,13b, and the support pad 539 is kept the same, the head gap of eachmagnetic head always contacts the magnetic card 1a, which provides goodwrite/read performance. The magnetic heads 13a, 13b are difficult toincline by using the two parallel flat springs 536a, 536b, even ifcentrifugal force is used. Once the positions of the magnetic heads 13a,13b are adjusted when the turntable 15 is stationary, the geometricalrelationship of the stationary condition is maintained, even if theturntable 15 rotates, which provides the same effect as Embodiment 39.

Embodiment 41

Another embodiment, in which the magnetic card effectively contacts themagnetic head, will be explained.

FIG. 62 shows the embodiment using another kind of spring instead ofusing the two parallel flat springs as described in Embodiment 40. InFIG. 62, two gimbal springs 536c, 536d are provided, which are commonlyused for a floppy disk drive, etc. A spacer 537c at the magnetic headside and a spacer 537d at the fixing part side are fixed respectivelybetween the gimbal springs 536d, 536d. The spacers 537c, 537d supportthe gimbal springs 536c, 536d to keep them parallel, so that themagnetic heads 13a, 13b are moved only vertically with the turntable 15.In Embodiment 40, the cantilever flat springs are used, and theconfiguration using gimbal springs also produces the same effect asEmbodiment 40, as well as reducing the apparatus size, even when thespring constant is low.

Embodiment 42

Another embodiment will be explained, in which the card holdingmechanism with a pressure pad provides effective contact of the magnetichead and the card.

FIGS. 63A and 63B show a supporting mechanism for the pressure pad 207.As shown FIGS. 63A, 63B, a pad gimbal 540 supports the pressure pad 207so as to have a degree of freedom of rotation. The pad gimbal 540 givesthe pressure pad 207 a degree of freedom of rotation around both thelong side and the short side directions of the card. The pad gimbal 540is connected to the pad frame 208 (not shown in the figures) through thepad spacer 541. In the card reader, the scanning locus of the rotationof the magnetic head should match the information track on the card.Therefore, after inserting the magnetic card 1a, the pressure pad 207 iskept stationary with the pad frame 208. For example, when the card ismoved in the long side direction for changing the information track onthe card, the pressure pad 207 and the pad frame 208 are required tomove in the same direction together with the card. Therefore, therigidity of the pad gimbal 540 should be high in the long side and theshort side direction. And the pressure pad 207 should have far lowerrigidity using porous polymeric materials like sponge or textilematerials like furfelt. The pressure pad 207 changes its form so as tocover and contact the card. The pressure force of the pressure pad 207is determined according to distance between the pad frame and themagnetic head. When the vertical rigidity of the pad gimbal 540 in thevertical direction with the contacting surface of the pressure pad islow, the elastic change of the pressure pad 207 is small, which causesthe magnetic head to not contact the magnetic card well enough formaintaining normal operation. Therefore, the vertical rigidity of thepad gimbal 540 should be higher than the vertical rigidity of thepressure pad 207.

Two types of the pad gimbals 540 are shown in FIGS. 63A, 63B. Asdescribed above, the rotating rigidity of the pad gimbal around the longside and the short side directions is set low. The vertical rigidity isset higher than the vertical rigidity of the pressure pad 207 in thedepth direction, and the horizontal rigidity in the horizontal directioncan be set higher.

In this embodiment, the pressure pad 207 is supported by the pad gimbal540 so as to rotate freely only around the long side and the short sidedirection. In case of using a plurality of magnetic heads, even if eachmagnetic head fixed on the turntable has an error in height adjustment,or if the pressure pad 207 is not set exactly vertical with the rotationshaft of the turntable, the pressure pad is controlled to make a desiredplane by the pad gimbal 540. Therefore, the magnetic head can contactthe magnetic card, even if each part of the apparatus is not adjustedexactly.

Embodiment 43

Another embodiment will be explained, in which the card holdingmechanism with a pressure pad provides effective contact of the magnetichead and the card.

FIG. 64 shows another configuration related to the supporting mechanismfor the pressure pad 207, which is used in Embodiments 39 and 42. Apivot 542 is provided on the back side of the pad gimbal 540. The pivot542 is provided on the opposite side of the side where the pressure padis fixed. Even if the pad gimbals, whose vertical rigidity is lower thanthat of the one explained in Embodiment 42, is used, the embodimentproduces the same effect as Embodiment 42 by providing the pivot 542.

Embodiment 44

Another embodiment will be explained, in which the card holdingmechanism with a pressure pad provides effective contact of the magnetichead and the card.

FIG. 65 shows another configuration related to the supporting mechanismfor the pressure pad 207, which is used in Embodiments 42 and 43. InFIG. 65, the pad gimbal has a frame fixing part 540a to be fixed to thepad frame, and a pad fixing part 540b for fixing the pressure pad 207.The pad fixing part 540b has a window in the inside area. The windowsize should be larger than the scanning area of the magnetic head. Thecard does not need to contact the pad gimbal 540. In the scanning areaof the magnetic head, the magnetic card should be always contacted byand supported by the pressure pad 207 and the magnetic head. In thescanning area of the magnetic head, the pad gimbal 540 should not touchthe card. The rotation axis, around which the pressure pad 207 isrotated, is almost the center of the pad gimbal. Since the magnetic cardand the pad gimbal 540 are very thin, the rotation axis of the pressurepad is almost the center of the magnetic card.

In case of using a plurality of magnetic heads, even if each magnetichead, fixed on the turntable, has an error in adjusting the height, orif the pressure pad 207 is not set exactly on vertical plane with therotation shaft of the turntable, the pad gimbal rotates and/or inclinesin some degree and controls the pressure pad 207 to form a desiredplane. A dislocation may occur between the scanning locus of themagnetic head and the information track on the card because of thedistance from the rotation axis of the pad gimbal to the magnetic card.In the apparatus described in Embodiment 42 or 43 with the thickpressure pad, the dislocation may occur beyond the allowed limit. Inthis embodiment, as the magnetic card and the pad gimbal 540 are verythin compared with the thickness of the pressure pad, the dislocationcan be minimized.

Embodiment 45

The following explanation will be related to the contact of the magnetichead and the magnetic card.

FIG. 66 illustrates a so-called button-type magnetic head having aspherical or a projected engaging part, which is used in the aboveembodiment. As shown in FIG. 66, the magnetic head 543 has a head gap543a, a friction surface 543b, and a taper 543c. The friction surface543b has a spherical or projected surface, having the head gap 543a as atop part, and the shape of the taper 543c is a part of a cone. Thefriction surface 543b is continued to the taper 543c smoothly. Theheight H of the taper 543c is set larger than the thickness of themagnetic card. The height H is determined based on the flatness of themagnetic card or the card feeding mechanism, etc.

FIGS. 67A to 67D show inserting the operation of the magnetic card tothe apparatus using the magnetic head 543 according to this embodiment.Before inserting the magnetic card, the magnetic head 543 remainstationary with or without the pressure pad 207 contacted. In thisembodiment, the case, in which the magnetic head contacts the pressurepad 207 and the magnetic card 1a cannot easily inserted, is explained.The embodiment can be also applied to the case, in which the magnetichead is not in contact with the pressure pad 207. As shown in FIG. 67A,the magnetic card 1a is inserted in the direction shown by an arrow Amanually or by the card feeding mechanism. At this time, the edge of themagnetic card 1a touches the taper 543c of the magnetic head 543. Whenthe magnetic card 1a is inserted deeply, the magnetic card 1a is movedalong the surface of the taper 543c to the friction surface 543b andfinally contacts the pressure pad 207 as shown in FIG. 67B. The magneticcard 1a is inserted in the wedge-shaped space between the frictionsurface 543b or the taper 543c and the pressure pad 207, and is moved tothe space between the pressure pad 207 and the friction surface 543b ofthe magnetic head by pushing up the pressure pad 207. The insertingprocedure of the magnetic card 1a is finished by adjusting its positionsuch that the friction surface 543b contacts the whole surface, so thatthe information can be written/read to/from the magnetic card 1a asshown in FIG. 67D.

The magnetic card 1a can be inserted smoothly by providing the taper543c to the magnetic head 543 without using the special mechanism whichmakes the space for the card. If the pressure pad 207 is set to be ableto contact the magnetic head 543, dust or contamination on the magnetichead can be removed by the pressure pad by turning the turntable (notshown in the figure) before inserting the magnetic card 1a.

In this embodiment, the magnetic head 543 is fixed on the turntable. Theembodiment can be applied to the configuration, in which the magnetichead 543 is fixed on the turntable through the spring, to produce thesame effect as the above configuration. In this case, the taper 543c isalso provided to the magnetic head 543, and the spring, instead of thepressure pad, can be bent and changed in shape to guide the magneticcard smoothly on inserting the magnetic card 1a.

Embodiment 46

In the following, a cleaning mechanism for removing dust orcontamination from the magnetic card will be explained.

As an example of the cleaning mechanism for removing dust orcontamination from the magnetic recording medium, two kinds of VTRcassette tape cleaners are commonly known; one of which includes apolishing sheet in the cassette case instead of the magnetic tape (drytype), and the other of which includes a polishing cloth wet by liquidpolisher (wet type). For cleaning a floppy disk, the dry type cleaner,which includes a polishing sheet instead of the floppy disk in thediskette case, is usually used.

There are some problems in using the above kinds of cleaners forremoving sticking dust on a magnetic card as follows:

(1) The recording medium for the card reader of the invention is exposedwithout being included in a cassette, etc. The magnetic card may easilybecome dirty by dust in the air, fingerprint, fat and oil, etc.

(2) The card reader of the invention has the driving roller for feedingthe card. When the driving roller touches polisher for cleaning, thedriving roller cannot feed the card accurately, which reduces write/readperformance of the data of the card.

FIG. 68 shows a dust remover according to the embodiment. A dust remover544 has a notch 544a, a friction surface 544b, and a taper 544c. Thefriction surface 544b has a spherical or projected shape and has thenotch 544a as a top part. The shape of the taper 544c is a part of acone. The friction surface 544b is continued to the taper 544c smoothly.Namely, the dust remover is desired to have almost the same shape as themagnetic head shown in FIG. 66. The height H of the taper 544c is setlarger than the thickness of the magnetic card to insert the magneticcard smoothly. These elements are made of ceramic materials such asalumina, titania, or zirconia, which have high abrasion-fastness, highrigidity, and high tenacity.

FIGS. 69A, 69B show examples of notch 544a of the dust remover. In FIG.69A, the notch 544a is shaped almost triangular, and the notch 544a inFIG. 69B is shaped almost circular. The same effect is obtained by usingboth types of notches. The notch is required to be shaped so that theangle T with the friction surface as shown in FIGS. 69A, 69B is lessthan 90 degrees.

FIG. 70 shows the dust remover 544 provided with the turntable 15. Theconfiguration shown in FIG. 70 is the same as the configurationdescribed in Embodiment 39. In addition to the configuration ofEmbodiment 39, the dust remover 544 is fixed to an adjusting holder 545for the dust remover and the holder 545 is mounted on the turntable 15.As well as the magnetic heads 13a and 13b, the position of the dustremover can be adjusted with the desired accuracy by the adjustingholder 545 as follows:

1) set the dust remover 544 on a plane, which includes each of the tipsof the magnetic heads 13a, 13b and is vertical with the rotation shaftof the turntable 15;

2) also set the dust remover 544 so that the notch 544a is placed on thetop; and

3) also set the notch 544a so that the center of the notch is on thecenter line of the scanning locus of each magnetic head.

In the following, the removing operation will be explained. FIG. 71shows the dust remover 544 for removing sticking dust or contamination.In FIG. 71, contaminations 546 are stuck on the magnetic card. The dustremover 544 mounted on the turntable is moved in the direction shown byan arrow B with the rotation of the turntable. The contaminations 546are scratched by the upper edge of the notch 544a and piled inside ofthe notch 544a.

In the dust remover of the invention, the contamination on the magneticcard must be scratched as described above. Even if the contamination onthe card produces some error in reading the information of the magnetichead, the dust remover traces the scanning locus and removes thecontamination. The normal information can be read by reading with themagnetic head again after removing the contamination. In case of usingtwo magnetic heads and mounting one dust remover, three tips are formedso as to keep the card on the flatter plane, which enables the magnetichead to write/read the information stably.

Embodiment 47

FIG. 72 shows another mechanism of the dust remover of the invention. Asupport spring 547, which has the same shape and the same characteristicas the long arm spring 30 supporting the magnetic heads 13a, 13b, isprovided with the dust remover. The same effect can be obtained inremoving the contamination by the notch of the dust remover 544 usingthe configuration, in which the magnetic head is supported by thespring. If the pressure force of the support spring 547 for the dustremover is set larger than the pressure force of the long arm springsupporting the magnetic heads 13a, 13b, the contamination can be removedmore effectively.

In this embodiment, the configuration using the long arm springs forsupporting the magnetic heads 13a, 13b and the dust remover 544 has beendescribed. The same effect can be obtained by the configuration usingtwo parallel flat springs, which is described in Embodiment 40.

Embodiment 48

Another embodiment will be explained for placing the dust remover.

FIGS. 73A, 73B, and 73C show three different examples of placements ofthe dust removers. The configuration described in the above embodimentis shown in FIG. 73A. In FIG. 73B, two dust removers are placed justbefore the magnetic heads 13a, 13b respectively. In this configuration,the contamination is removed more effectively than the configurationshown in FIG. 73A. FIG. 73C shows another configuration, in which themagnetic heads 13a, 13b and the dust remover 544 are placed with thesame intervals between each other. This configuration not only removesthe contamination from the magnetic card, but also prevents the cardfrom contacting the turntable.

Embodiment 49

In the present embodiment, an explanation is made of a detailedconfiguration of the magnetic head which improves the contact conditionto the magnetic card in the magnetic card reader and the gimbal springto support the head.

In FIG. 1, the magnetic heads 13a and 13b on the turntable 15 wereloaded on the gimbal spring 19. In this system in FIG. 1, the magneticheads 13a and 13b should be light-weight. In addition, it is assumedthat the gimbal spring 19 should be capable of moving just up and downand overcoming the moment which will incline the magnetic heads 13a and13b to the outside according to the centrifugal force produced byrotation of the turntable 15. The gimbal spring 19 should further keepthe magnetic heads 13a and 13b in a proper condition. In the case wherethe turntable 15 rotates at a low speed in low recording track density,there are few problems. However, in the case where the turntable 15rotates at a high speed due to a reduction of the access time and therecording track density substantially increases due to the storagecapacity, the inclination of the magnetic heads 13a and 13b causes animproper track positioning and a bad contact condition between themagnetic heads 13a and 13b and the magnetic card 1a.

In this embodiment, there follows a description to solve the foregoingproblems.

FIG. 74 shows a perspective view of the portion of loading the magnetichead in the present invention. FIG. 75 shows a cross section taken online A--A of FIG. 74. The magnetic heads 13a and 13b are loaded on thegimbal spring 19 and attached to the turntable 15. The magnetic heads13a and 13b are set up at a height of sticking out a little on thesurface of the turntable 15. The centers of gravity 548a and 548b (Thecenter of gravity 548b is not shown in the figure) of the magnetic heads13a and 13b are located at a distance of H1 from the gimbal spring 19. Abalance weight 549 is installed below the gimbal spring 19. The centerof gravity 550 is located at a distance of H2 from the gimbal spring 19.

In the case where this apparatus reads and writes the information on themagnetic card 1a, the turntable 15 rotates around the rotation shaft 16in the direction of arrow C at a predefined speed according to the DCmotor 22. The magnetic card 1a and the magnetic heads 13a and 13b thencause friction.

Herein, the centrifugal force F1 is applied to the centers of gravity548a and 548b of the magnetic heads 13a and 13b. The magnetic heads 13aand 13b then tend to incline towards the outside of the turntable 15.The moment M1 which will cause the incline is expressed as follows:##EQU1## m1: mass of the magnetic heads 13a, 13b r1: radius of rotationof the magnetic heads 13a, 13b

ω1: angular velocity of the magnetic heads 13a and 13b

Simultaneously, the centrifugal force F2 is applied to the center ofgravity 550 of the balance weight 549. The balance weight 549 theninclines towards the outside of the turntable 15. The moment M2 whichwill cause the incline is expressed as follows: ##EQU2## m2: mass of thebalance weight 549 r2: radius of rotation of the balance weight 549

ω2: angular velocity of the balance weight 549

Herein, when the values of the two moments M1 and M2 are equal, theywill offset and thus the magnetic heads 13a and 13b don't incline. Eachradius of rotation, r1 and r2, is set to be equal, and each of theangular velocities ω1 and ω2 is also set to be equal in the abovementioned expressions (16) and (17). Therefore, so as to obtain theexpression M1=M2, the following expression should be made.

    m1×H1=m2×H2                                    (18)

Embodiment 50

There is shown a case of improving the dynamic contact condition. FIGS.76A and 77B are cross sections of another embodiment of the magnetichead of the present invention. In FIG. 75, the gimbal spring 19 isadhered to the surface of the turntable 15 horizontally. In the presentembodiment, the gimbal spring 19 adheres inclined on the side of therotation shaft 16. The distance of the centers of gravity 548a and 549bfrom the gimbal spring 19 is assumed here to be H1 as it was inEmbodiment 49.

Herein, when the turntable 15 rotates, the centrifugal force is appliedto the magnetic heads 13a and 13b. Then, the moment M1 which causes themagnetic heads 13a and 13b to incline toward the outside of theturntable 15 is produced. The size of M1 is shown according to theexpression (16).

In general, the size of the moment M which is applied from the outsideto the gimbal spring and the inclined angle θ of the gimbal spring havea proportional relationship in the case where the inclined angle issmall. The proportional constant is assumed to be k, and the followingexpressions can be made.

    M=kθ                                                 (19)

namely,

    θ=M/k                                                (20)

The proportional constant k is determined according to the form and thematerial of the gimbal spring. When the proportional constant is assumedto be k1, the inclined angle θ1 of the gimbal spring 19 in case ofapplying the moment M1 is expressed as follows:

    θ1=M1/k1                                             (21)

That is, in the case where the gimbal spring 19 adheres inclined on theside of the rotation shaft 16 on the turntable 15 with an inclination ofθ1, when the turntable 15 rotates and the centrifugal force applies tothe magnetic heads 13a and 13b, the magnetic heads 13a and 13b stand ina proper condition as shown in FIG. 76B. Thus, the magnetic heads 13aand 13b have a good contact condition with the magnetic card 1a.

Embodiment 51

Further, there is shown another case of improving the dynamic contactcondition. FIGS. 77A and 77B show a cross section of another embodimentof the magnetic head of the present invention. In FIGS. 74 and 75, thetop surface planes of the magnetic heads 13a and 13b are parallel withthe plane of the gimbal spring 19. In FIG. 77A, the top surface planesof the magnetic heads 13a and 13b incline on the side of the rotationshaft 16. The distance of centers of gravity 548a and 548b from thegimbal spring 19 is assumed here to be H1 as it was in Embodiment 49.

Herein, when the turntable 15 rotates, the centrifugal force is appliedto the magnetic heads 13a and 13b as in FIG. 75. Then, the moment M1which causes the magnetic heads 13a and 13b to incline to the outside ofthe turntable 15 is produced. The size of M1 is shown by the expression(16).

As explained in Embodiment 50, when the proportional constant of thegimbal spring 19 is assumed to be k1, the inclined angle θ1 of thegimbal spring in case of applying the moment M1 is expressed as follows:

    θ1=M1/k1                                             (22)

That is, in the case where the top surface planes of the magnetic heads13a and 13b incline on the side of the rotation shaft 16 by θ1 inadvance, when the turntable 15 rotates and the centrifugal force isapplied to the magnetic heads 13a and 13b, the top surface planes of themagnetic heads 13a and 13b become in the proper condition as shown inFIG. 77B. Thus, the magnetic heads 13a and 13b can have a good contactcondition with the magnetic card 1a.

Embodiment 52

The following description deals with a track in the case of reading andwriting in high density with the magnetic head which rotates with apredefined radius. A prepaid telephone card, a prepaid ticket machinecard, a commuter pass or other exchangeable rectangular magnetic cardwhich has no holes can be used for this application.

In order to implement these cards, the following problems should besolved.

(a) When there is no clearance between the symmetric innermost tracks ofthe magnetic or optical card, because of the positioning error of thecard related to the mechanic accuracy of the card holding mechanism, therecording areas of the innermost tracks overlap. Then, there occurs across talk from the adjacent tracks which pick up the leaking signal. Inthis case, the normal operation of reading and writing cannot beexecuted.

(b) When the magnetic or optical card is inserted backward, the cardreader detects that it is not inserted in a normal way. Then, the cardreader ejects the card from the card reader automatically. In this case,the user should manually insert the card again in a normal way.

In the present embodiment, there is shown a case of the magnetic cardand the magnetic head. However, the present embodiment is alsoapplicable to the case of the optical card and the optical head.

FIG. 78A shows the recording tracks as shown in FIGS. 12A to 12C. Thehead assembly 280 which loads the magnetic heads 13a and 13b relativelymoves on the center line X-Y in the horizontal direction of the magneticcard 1a by an equal pitch (the length P corresponds to a track pitch). Aplurality of recording tracks 63 have radius R. In FIG. 78A, a clearanceI₀ at the closest position between the innermost track 63c and the otherinnermost track 63d is set according to the recording angle α and theexpression (23) below in the case where the total track number isassumed to be N. Further, O₁ and O₂ show the center of the circle whichforms the front track 63e and the rear track 63f. As described inEmbodiment 10, areas A, B, and C show unusable area which crosses withthe circles of other recording tracks and unused areas. (same for FIGS.78B and 78C). The distance between O₁ and O₂ is assumed to be I.

    I=(N/2-1)P

    I.sub.0 =2RCOS α-(N/2-1)p                            (23)

For an extreme example, in the case where the above mentioned I₀ issmaller than the track pitch P, FIG. 78B shows the recording track whenI₀ =0. In FIG. 78B, at the record beginning portion and the endingportion of the innermost tracks 63c, 63d surrounded by the dottedcircle, according to the mechanical accuracy of the feeding mechanism186 as in FIG. 27 which is a card holding mechanism, a signal overlapsand is written on the record ending portion and the beginning portion ofthe other innermost track 63d. In the case where the written signal isread or written again after the above mentioned magnetic card 1a isinserted, it is impossible to execute the normal reading and writingprocess.

Furthermore, in FIG. 78C, unless the recording beginning portion and theending portion of the innermost tracks 63c and 63d overlap, there isshown a recording track in the case where the I₀, which is the closestdistance, is shorter than the track pitch P. In FIG. 78C, at the recordbeginning portion and the ending portion of the innermost track 63c and63d surrounded by the dotted circle, there occurs a cross talk betweenthe adjacent tracks which pick up signal from the recording trackaccording to the magnetic interference. Thus, it is difficult to get theproper output signal. In the present invention, a clearance I₀ at theadjacent position of the innermost tracks 63c and 63d as shown in theexpression (23) is set to have more than the track pitch. Further, therelationship of the expression (24) and the recording angle a having thetotal extension of the track M as shown in embodiment 10 are set. As aresult, it is possible to realize the recording track format of themagnetic card which makes the steady write and read process possiblewith achieving the maximum efficiency. ##EQU3##

Embodiment 53

The following description deals with an effective usage of areas otherthan the data recording area in the card. In the present embodiment, themagnetic card and the magnetic head are used. However, it is alsoapplicable to the case of the optical card and the optical head.

FIG. 79 shows the magnetic card 1a equivalent to that in Embodiment 52.Further, FIG. 79 shows a recording track which uses a part of areas of Aand B. Areas A and B are unusable areas which cross with anotherrecording track. In this embodiment a part of areas A and B is used as arecording area of the front track 63e and the rear track 63f. In FIG.79, I₁ shows the closest distance between the record beginning portionand the ending portion of the front track 63e and the rear track 63f. Asdescribed in Embodiment 52, the length of I₀ is assumed to be more thantrack pitch P. O₁ and O₂ show the centers of the circles which form thefront track 63e and the rear track 63f. m₀ and n₀ on each circle are thepoints in the area B having the distance I₁. m₁ and n₁ are theintersections with the dotted line which shows the area B. m₂ and n₂, m₃and n₃ on the area A are the points equivalent to the m₀ and n₀, m₁ andn₁. The address mark which shows a track address or the front track 63eor the rear track 63f is recorded on the recording track of the arcsbetween the points m₀ and n₀ and the points m₁ and n₁. The same processis carried out on the recording track of the arcs between the points m₂and n₂ and the points m₃ and n₃. Further, as in Embodiment 10, the areasA and B have a high frequency of causing flaw and spots by the hands inits use. Therefore, in this area, a simple pattern is recorded. Thesimple pattern is data which are incapable of causing error in this area(for example, `00`, `AA`, or `FF` in case of the MFM recording).

The operation of the card reader 160 will now be described. FIG. 80Ashows a flow chart of a sequence until the magnetic card 1a is insertedto the card reader 160 and the magnetic heads 13a and 13b loaded on thehead assembly 280 as shown in FIG. 12A then determine position on thefront track 63e. Herein, the address marks of the front track 63e andthe rear track 63f are referred to as `00` and `AA`, respectively. Themagnetic card 1a is inserted as described in Embodiments 18, 19 and 20.The optical sensor 192 is mounted at the edge of the card end guide 190.The optical sensor 192 detects that the card reaches a fixed position ofthe card holding mechanism 186. When the detection signal is output, theturntable 15 starts to rotate. The address mark is then read accordingto the magnetic heads 13a or 13b. Herein, when the `AA` pattern isdetected, the magnetic head 13a or 13b is on the rear track 63f.Therefore, the head assembly 280 is moved to the front track 63e. When`00` pattern is detected, the head assembly 280 stays in position andbecomes ready to operate. The head assembly 280 waits for the indicationsignal of the outside controller not shown in the figure.

FIG. 80B shows another flow chart for positioning the magnetic heads13a, 13b on the front track 63e. As described in Embodiment 28, it ispossible to read addresses recorded on the recording tracks 63 and/ortrack information on the outermost tracks (the front track 63e and/orthe rear track 63f). By reading the track addresses and/or the trackinformation, the magnetic heads 13a, 13b can be positioned at the fronttrack 63e.

It has been described that the head assembly 280 relatively movesagainst the magnetic card 1a in the carriage. On the other hand, it isalso possible that the carriage loaded with the magnetic card 1arelatively moves against the head assembly 280.

FIGS. 80C and 80D show flow charts for positioning the magnetic heads13a, 13b at the front track 63e. As described in Embodiment 28, it ispossible to provide a procedure having track address information of themagnetic card 1a. The procedure can reverse the track address front torear and rear to front. The track address received from the outsidecontroller (not shown) for track detection operation can be reversed bythe procedure. In this case it is not necessary to move the headassembly 280 or the carriage when either `AA` pattern or `00` pattern isdetected. When `AA` pattern is detected, the track address is reversedby the procedure before the positioning the magnetic head.

As described before, the card reader will be ready when the magneticheads 13a, 13b are positioned at the front track 63e which is theclosest track to the card inlet 170. It is also possible that the cardreader will be ready when the magnetic heads 13a, 13b are positioned atthe rear track 63f which is the farthest track from the card inlet 170.Even for the later case, any one of the four sequences shown in FIGS.80A to 80D can be applied if the detection step of `AA` pattern isreplaced by the detection step of `00` pattern, and "front track 63e" isreplaced by "rear track 63f" in the flow charts.

The card reader of the present invention sets the clearance between theinnermost tracks of the magnetic card or the optical card to have adistance of more than the track pitch. As a result, it is possible toreduce the mechanical accuracy of the holding mechanism of the magneticcard or the optical card. Further, it is possible to read and writeeffectively without influence by the cross talk between the adjacenttracks.

Furthermore, in the track format, both or either of the front track andthe rear track in the magnetic card or the optical card are set to belonger than the other track. Then, the address mark which shows thetrack address or the front track or the rear track is recorded. As aresult, the card reader is able to detect that the magnetic card or theoptical card is inserted backward. Thus, the read and write process canbe executed even if backward insertion occurs. That is, the properinsertion need not be carried out again.

Embodiment 54

There follows a description of a configuration, which reduces accesstime and improves reliability, for mounting plural heads on a singlecircumference. Conventionally, in the case where the recording area onthe card is limited, the above mentioned case has not been taken accountof.

In the present embodiment, there is shown a case of the magnetic cardand the magnetic head. However, it is applicable to the case of theoptical card and the optical head.

FIG. 81A shows an arrangement of the recording tracks 63 on the magneticcard 1a. FIG. 81B shows an arrangement of the magnetic heads 13a and 13bon the turntable 15. Dotted lines show loci 551 of the magnetic heads13a and 13b.

In FIGS. 81A and 81B, in case of arranging the recording tracks 63 in ashape of the arc on the magnetic card 1a, two recording tracks 63 arearranged symmetrically on the locus 551 of the magnetic heads 13a and13b. In order to correspond to two recording tracks 63, the magneticheads 13a and 13b are also arranged symmetrically. Herein, when therecording electric current of the same waveform is simultaneouslyapplied to the magnetic heads 13a and 13b, the same data can be recordedon the two recording tracks 63 on the locus 551.

Herein, by thus recording, all the recording data on the magnetic card1a are recorded on two tracks. Therefore, even though the readout fromone track fails, the data recorded on another track can be read out.Accordingly, the reliability of the magnetic card improves. Further,since data is recorded on two recording tracks 63 simultaneously in thecase of recording data, the time for recording will not increase. Sincetwo recording tracks 63 are recorded in one recording electric currentwaveform, the operation at the time of recording can be simplified.

Embodiment 55

In the above embodiment, two heads are spaced from each other by anangle of 180 degree. That is, there was shown a case of reading andwriting symmetrically to the center of the circle. In the presentembodiment, there is shown a case where this angle is assumed to bebelow 90 degrees, for example.

In Embodiment 55, the magnetic cards and the magnetic heads can be used.However, it is applicable to the case of the optical card and theoptical head.

FIG. 82A shows an arrangement of the recording tracks 63 on the magneticcard 1a. FIGS. 82B and 82C show an arrangement of the magnetic heads 13aand 13b on the turntable 15 not shown in the figure. FIG. 82D shows atime chart when the magnetic heads 13a and 13b record data. In thefigure, the loci 551 of the magnetic heads 13a and 13b, a recording area552a of the magnetic head 13a, and a recording area 552b of the magnetichead 13b are shown. Period 553 shows a time in which the magnetic head13a moves on the recording track 63. Period 554 shows a recording timein which the magnetic heads 13a and 13b record data. Period 555 is atime in which the magnetic heads 13a and 13b move without recording. 2αis a center angle of the recording track 63. β is a center angle betweenthe magnetic heads 13a and 13b. FIG. 83 shows an arrangement of themagnetic heads 13a, 13b, 13c, and 13d on the turntable 15 in the casewhere the recording track 63 is arranged as in Embodiment 54. Themagnetic head 13c records data in the recording area 552c, and themagnetic head 13d records data in the recording area 552d.

In FIG. 82A, two recording tracks 63 are not arranged on one locus 551of the magnetic heads 13a and 13b in the case of arranging the recordingtracks 63 in the shape of an arc. Under such arrangement, data cannot berecorded simultaneously on two recording tracks 63 with the arrangementof the magnetic heads 13a and 13b as in Embodiment 54. Therefore, themagnetic heads 13a and 13b are arranged as shown in FIGS. 82B and 82C.In the figure, 2α is a center angle of the recording track 63. Thecenter angle of the magnetic heads 13a and 13b is assumed to be β.Herein, β is determined so as to obtain the expression of 2α=(β·2)·k.Herein, k is an integer. FIG. 82B shows an arrangement when k=1. FIG.82C shows an arrangement when k=2. A moving direction of the magneticheads 13a and 13b used for the explanation is shown in the figure byarrows. FIG. 82D shows a time for recording data in the arrangement whenk=2.

In the arrangement of FIG. 82B in the case where k=1, the recording isstarted when the magnetic head 13a reaches to the beginning of therecording track 63. At this time, the magnetic head 13b is situated inthe middle of the recording track 63. It is possible to record until themagnetic head 13a reaches the middle of the recording track 63. When themagnetic head 13a reaches the middle of the recording track 63, themagnetic head 13b reaches the end of the recording track 63. As shown inFIG. 82B, the former part of the recording track is the recording area552a of the magnetic head 13a and the latter part is the recording area552b of the magnetic head 13b.

In the arrangement of FIG. 82C in the case where k=2, the recording area552a of the magnetic head 13a is divided into two parts. When themagnetic head reaches to the beginning of the recording track 63, themagnetic head 13b reaches the point of one fourth of the recording track63. The recording is started from this point and stops when the magnetichead 13a reaches the point of one fourth of the recording track 63.Next, when the magnetic head 13a reaches the middle of the recordingtrack 63, the recording is started. Then, the recording ends when themagnetic head 13a reaches the point of three fourth of the recordingtrack 63. Herein, the magnetic head 13b records from the point of threefourth of the recording track 63 to the end of the recording track 63.FIG. 82D shows this operation on the time axis. Period 553 shows thetime during which the magnetic head 13a moves on the recording track 63.The period 553 is divided equally into the four periods. Data isrecorded during the two divided periods 554. Data is not recorded duringthe two divided periods 555.

Furthermore, it is apparent that the above mentioned system can beadopted in the magnetic card or the optical card which has thearrangement of the recording track 63 of the system provided inEmbodiment 54. In this case, the same number of magnetic heads arearranged for each of the two recording tracks 63. The correspondingmagnetic heads for recording in the two recording tracks 63 should thenbe arranged in the position symmetrical to the center of the rotation.In FIG. 83, there is shown a case where two magnetic heads are arrangedin each recording track 63. The magnetic heads 13a and 13b are arrangedin one recording track 63, and the magnetic heads 13c and 13d arearranged in the other recording track 63. The magnetic head 13c isarranged in the position symmetrical to the magnetic head 13a. Further,the magnetic head 13d is arranged in the position symmetrical to themagnetic head 13b. The recording is started when the magnetic heads 13aand 13c reach the beginning of the recording track 63. The recordingthen ends when the magnetic heads 13b and 13d reach the end of therecording track 63. Thus, it is possible to record the same datasimultaneously in each of the four recording areas dividing tworecording tracks 63 equally into four.

Thus, this embodiment has an advantage of reducing the access time forreading and writing.

It is apparent that the above mentioned system can be adopted in thecase where more than three magnetic heads are used. In order to arrangeN number of magnetic heads, the expression 2α=(β·N)·k should be used.Herein, k is an integer.

Embodiment 56

There follows an explanation of a cleaning card for cleaning themagnetic head in the magnetic card reader. In Embodiment 39, anexplanation is made for the conventional cleaning tape or the cleaningsheet. Since the magnetic recording medium is protected by the cassettein the conventional apparatus, the spot or dust on the magnetic head ismainly an adhesive mist collection in the recording medium. Therefore,the head cleaner for these apparatus can easily specify thecontamination which adheres to the magnetic head. Cleaning of the headis carried out by using the corresponding type of abrasive. Herein, itis desirable to use an abrasive whose particle size is very small.Further, it is desirable to use the abrasive for finishing the magnetichead making. However, the concept of these tapes or sheets cannot beused for the magnetic card without hesitation. There are some problemsto be solved as described in Embodiment 39. In the present embodiment,an explanation is made for a new cleaning card corresponding to themagnetic card in the present invention.

There follows an explanation of the head cleaning card of the presentinvention, more specifically, the configuration of the cleaning portionof the magnetic head.

FIG. 84A shows a view of one embodiment of the head cleaning card. Abase film 556 is composed of a material such as a polyethyleneterephtalate (PET). The outside form, such as the width, the length, andthe thickness, is almost equal to that of the card reader. Abrasives557a and 557b are varnished on this base film 556. The abrasive 557awhose particle size is under 1 micron is for finishing with a highprecision. The abrasive 557b whose particle size is above 1 micron isfor finishing with a middle precision. The materials of these abrasivesare alumina, chromium oxide, cerium oxide, silicon carbide, siliconboron, boron nitride, iron oxide, diamond and other mixtures. For anabrasive, adhesive materials are mixed so as to varnish these particleson the sheet without being removed.

The operation will now be described. The head cleaning card is insertedto the card reader in the direction of the arrow A. In FIG. 84A, a locus558a is for the magnetic head (not shown in the figure) after the headcleaning card is inserted. A locus 558b is for the magnetic head whenthe head cleaning card is carried or positioned to the rear end in thecard reader.

After the head cleaning card is inserted, the order of polishing wouldbe reversed by first contacting the abrasive 557a whose particle size issmall, then by second contacting the abrasive 557b whose particle sizeis large. To prevent the reverse order, the card moves at a high speedso that the magnetic head reaches to the locus 558b which is thestarting point of cleaning. When the card moves to position the magnetichead at the locus 558b, the magnetic head does not need to rotate. Afterpositioning to the locus 558b, the magnetic head starts the rotation andthe head cleaning card moves in the direction of arrow B for the orderlycleaning operation from the locus 558b to the locus 558a. Here, the cardremoves the contamination which is adhered to the magnetic head by arubbing contact.

In the present embodiment, when the magnetic head is in rubbing contactwith the abrasive 557b, there is an effect of removing the contaminationhaving a relatively large volume such as fixed oils and fats likefingerprints. Further, there is an effect of finishing and removing theadhesive materials according to a mechanical reaction from the magneticcard and so forth in the case where the abrasive 557a is in rubbingcontact. Thus, there is an advantage of preventing the abrasive 557afrom being choked and actuating the effective cleaning of the magnetichead.

Embodiment 57

There is shown another example of the cleaning card. In FIG. 84B, thelength L of the abrasive 557a is set to be larger than a diameter D ofthe locus 558a or 558b of the magnetic head. At the stage of finishingwith the abrasive 557a, there is an advantage of avoiding damage on thesurface of the magnetic head with the abrasive 557b. Further, in theabrasive 557b, since its particle size is large, the magnetic head iseasily cracked. When the relative speed of the head cleaning card isfinite and the length L of the abrasive 557a is extended, it is possibleto control the time for polishing with abrasive 557b and to gain theproper head cleaning effect.

Embodiment 58

FIG. 84C shows further another embodiment. In this embodiment, anonwoven fabric 559 in an almost L shape is arranged on the cleaningcard provided in Embodiment 56 or 57. The nonwoven fabric 559 has aneffect of catching the contamination and particles caused in the case ofremoving the contamination by using abrasive 557a and 557b. Further, anultimate effect of finishing can be attained on the locus 558a of themagnetic head. Further, in the preceding embodiments, a dry abrasive isshown. However, this embodiment is applicable to the case of a wetabrasive by wetting the nonwoven fabric with a liquid such as water.Further, a better cleaning effect can be attained by wetting thenonwoven fabric with an organic solvent, such as alcohols, benzine,acetone and so forth.

Embodiment 59

There is shown a case of the cleaning card when the card driving rollerof the card feeding mechanism is applied. FIG. 85A is a drawing of oneof embodiment. In FIG. 85A, a contacting part 560 is installed for thecleaning card in the configuration of Embodiments 56 to 58 to contactthe driving roller. The contacting part 560 is installed in thedirection of the longer part of the head cleaning card at a fixeddistance. The distance is selected to be wider than the diameter D ofthe locus 558b of the magnetic head. The thickness is configured so asto obtain higher than a few 10 to 100 microns from the surface composedof the abrasive 557a, 557b and the nonwoven fabric 559. The material ofthe contacting part 560 is synthetic rubber such as neo-plain rubber orpolymeric resin such as urethane.

FIGS. 86A and 86B are the views for explaining the operation of thepresent embodiment. FIG. 86A shows an example of the card feedingmechanism of the card reader. When the head cleaning card is inserted tothe card reader, the head cleaning card is held by the driving roller184 and the guide roller 185. The head cleaning card is fed in thedirection of arrow A and B with the turn of the driving roller 184. Thecontacting part 560 installed at the head cleaning card contacts withthe driving roller 184.

The operation will now be described. FIG. 86B shows an elevational viewin the case where the head cleaning card is held by the driving roller184 and the guide roller 185. In FIG. 86B, black spots shows dust andpolishing powder 561 which is produced during the cleaning of themagnetic head. As shown in the figure, since the contacting part 560 isthick, the abrasives 557a, 557b, the dust and the polishing powder 561produced during the head cleaning do not touch the driving roller 184.Therefore, the abrasives 557a and 557b do not rub the driving roller 184and the surface of the driving roller 184 is not damaged. Accordingly,this method will substantially reduce a danger of changing greatly thefriction coefficient of the driving roller 184 from the original designvalue and worsening the feeding precision sharply when the magnetic cardis operated after the cleaning. In addition, it will prevent the dustand the polishing powder 561 from adhering on the driving roller 184 andtranscribing on the magnetic card again. Furthermore, since a part ofthe abrasives 557a and 557b which contact the magnetic head isconfigured as concave by the contacting part 560, it is possible tolessen chances for contacting contamination when the head cleaning cardis kept or transmitted outside of the card reader.

Embodiment 60

FIG. 85B shows another embodiment of the cleaning card. The contactingpart 560 is configured in a U shape. As the material of the contactingpart, nonwoven fabric is used. The width and thickness of a notch of thecontacting part 560 are set almost equivalent to these in Embodiment 59.Herein, the cleaning card can remove the dust or mists adhered on thedriving roller 184 since the contacting part 560 contacts the surface ofthe driving roller 184.

Embodiment 61

In FIG. 85C, there is shown another embodiment of the cleaning card. Inthe figure, the contacting part 560 is configured in the frame shapewhich has a small square space inside. The same effects as described inthe preceding embodiments can be achieved.

The cleaning card provided in each of the above mentioned embodimentshas an effect of avoiding the inferiority of the read/write ability ofrecording data caused by contamination because it is possible to removethe contamination adhering on the magnetic head such as dust or mists inthe air, fingerprints, oil, and so on. Further, the cleaning cardaccording to the present invention has an effect of preventing the lifecycle of the magnetic head from being reduced by polishing the magnetichead unnecessarily.

Embodiment 62

In this embodiment, another feeding mechanism, which alters the feedingmechanism 186 having the driving roller 184 and the guide roller 185stated in Embodiment 20, will be described.

In the card reader 160 of FIG. 24, since the distance between the frontpanel 169 and the driving roller 184 is long, the depth of the cardreader 160 is long. A coil spring for pressing the guide roller 185 ontothe driving roller 184 is installed. Space for this coil is needed.

A mechanism in this embodiment is for downsizing the apparatus, makingthe action of the insertion of the card into the card reader smooth andgiving enough pressure for feeding the card to the feeding mechanism.

FIG. 87 shows a perspective view of another card feeding mechanism ofthe present invention. FIGS. 88A, 88B and 88C show partial sectionalviews of the feeding mechanism.

In FIG. 87 and FIGS. 88A to 88C, pressure springs 562 are installed atthe both sides of the insertion part. The pressure springs 562 can beturned in the direction of arrow A or arrow B by a pin 563 fixed to thecarriage base 189. Front edges 562a of the pressure springs 562 arecurved and they are against the driving roller 184. Back edges 562b atthe opposite side of the pressure springs 562 are curved into holes 564of the carriage base 189. Usually, the pressure springs 562 are turnedin the direction of arrow B as shown in FIG. 88A by the weight balanceand the back edges 562b contact the holes 564. In this case, the frontedges 562a do not contact the driving roller 184 or contact it only alittle.

When the magnetic card 1a is inserted and the edge of the magnetic card1a contacts the back edges 562b of the pressure springs 562, thepressure springs 562 turn in the direction of arrow A as shown in FIG.88B. When the magnetic card 1a is inserted deeply as shown in FIG. 88C,the front edges 562a are pushed toward the driving roller 184 stronglyand then friction is generated. The magnetic card 1a can be fed into theapparatus without slipping from the driving roller 184 because of thisfriction. If a sensor (not shown) detects that the magnetic card 1a issufficiently inserted, the driving roller 184 starts rotating in thedirection of arrow C and the magnetic card 1a is moved toward arrow D,that is inside of the apparatus. In this way, the apparatus can bedownsized and the card can be fed smoothly without being pushed toomuch.

Embodiment 63

FIGS. 89A to 89C show sections of another embodiment of the feedingmechanism.

Although the front edges 562a of the pressure springs 562 are curved inFIG. 87, the front edges of the pressure springs 562 are bent toward thedownside in this embodiment. A pin 565 supports a pressure roller 566 torotate toward both directions. Other structures are the same as those inFIG. 87. Usually, the pressure roller 566 does not contact the drivingroller 184 or contacts it only a little.

When the magnetic card 1a is inserted and the edge of the card contactsthe back edges 562b of the pressure spring 562, the pressure spring 562rotates in the direction of arrow A as shown in FIG. 89B. When themagnetic card 1a is inserted deeply as shown in FIG. 89C, the pressureroller 566 is pushed toward the driving roller 184 strongly and thenfriction is generated. The magnetic card 1a can be fed into theapparatus without slipping from the driving roller 184 because of thisfriction. If a card sensor (not shown) detects that the magnetic card 1ais sufficiently inserted, the driving roller 184 starts rotating in thedirection of arrow C and the magnetic card 1a is moved toward arrow D,that is inside of the apparatus. The pressure roller 566 rotates in thedirection of arrow E.

Since the pressure roller 566 rotates at the same time as the feedingthe magnetic card 1a in this embodiment, the load for feeding themagnetic card 1a can be lessened. Accordingly, the power for drivingmotor can be small and the magnetic card 1a is not damaged, which is aneffect of the present invention. Since the pressure roller 566 rotateswhen the magnetic card 1a is inserted, only small power is needed forinsertion, which produces another effect that the operation can besmooth.

It is also acceptable to install a roller like the pressure roller 566at the back edge 562b of the pressure spring 562. By installing theabove roller, the load of movement of the magnetic card 1a can befurther lessened and a possibility of the magnetic card 1a being damagedcan be further lessened, which is another effect of the presentinvention.

Embodiment 64

When the distance between the pin 563, which is the center of therotation, and the front edge 562a, or the distance between the pin 563and the pressure roller 566 is shorter than the distance between the pin563 and the back edge 562b, the power caused by the magnetic card 1a forlifting the back edge 562b is multiplied. Then the multiplied power isconveyed to the front edge 562a or the pressure roller 566. Namely,there is an effect that a large power for feeding the magnetic card canbe obtained.

Embodiment 65

Although the driving roller 184 contacts the card from side to side inFIG. 87, it is also acceptable for a driving roller 567 to contact onlythe both edges of the card as shown in FIG. 90.

The recording track 63 on the magnetic card of the present invention isshown in FIG. 91. Since the driving roller 567 and the magnetic card 1acontact each other only at the outside of a range F, it is possible toprevent the dust and stain which would be conveyed by the magnetic cardfrom reaching the driving roller 567 to the magnetic head. It is alsopossible to protect the recording track 63 by preventing the drivingroller 567 from getting damage or stain, which means that data can beprotected.

Regarding the material of the driving roller 567, it is acceptable touse a material which gives a slightly convex and concave surface of themagnetic card as well as a material, such as rubber that is notslippery. For example, metal material whose surface is sprayed withceramic, metal material whose surface is slightly concave and convexmade by etching or form rolling, metal material whose surface has veryfine needles and metal material whose surface has a sawtooth waveformare acceptable.

Embodiment 66

Other embodiments of the card support mechanism which has the cardpositioning mechanism where less parts are used, and which has highaccuracy in positioning the card, will now be explained.

When a card stores a large amount of data, its data recording density isvery high. In order to perform a random access to the above card, it isimportant to maintain the same relative positional relation between thecard and the head. In the feeding mechanism of FIG. 27 described above,the following method was used to maintain the same positional relation.The card 161 is received by the card end guide 190 on the carriage base189 and fixed by the pad frame 208. Then, the optical sensor 258 detectsa positioning error of the card by using the positioning mark 260 on thecard 161 and corrects the positioning error. In this method, it isnecessary to use the stepping motor 221 to perform servo control forpositioning the card. An expensive stepping motor of great precisionshould be used in this method. Besides, the amount of hardware used inthis method is large.

In the card reader of this embodiment, the card is moved while beingheld between the carriage base and the card holder which faces thecarriage base. The carriage base is restricted to move only in specificdirections by the guide mechanism.

More than two holes for positioning the card are on the card. There arepins at the positions corresponding to the holes on the carriage base.The card is fed with the pins inserted into the holes. The accuratepositional relation between the card and the carriage base can bemaintained by the above method. To insert the positioning pins into thecard, the card holder is moved with the carriage base towards thecarriage base. With this movement of the carriage base and the cardholder, the card held between the carriage base and the card holder isalso moved toward the carriage base. Further, the positioning pins canmove upward and downward with respect to the carriage base.

FIG. 92 shows a perspective view of the card holder of the card readerof this embodiment. FIGS. 93A and 93B show a section of the card holderseen at a line A--A in FIG. 92. FIG. 94 shows a perspective view of thecarriage base 189 described later.

The magnetic card 1a, the driving roller 184 for feeding the card 1a,the guide roller 185 placed against the driving roller 184, the carriagebase 189 having a guide rod 220 at the side and moving in the directionof X-Y, the stepping motor 221 and the lead screw 222 which is combinedwith the shaft of the stepping motor 221 are shown in FIG. 92.

The needle 219a and the pre-load spring leaf 219b are installed at theedge of the carriage base 189 as shown in FIG. 93A. The lead screw 222is connected with the needle 219a. The pre-load spring leaf 219bprovides pressure to the connection of the lead screw 222 and the needle219a to hold them together. Four pins 568a, 568b, 568c and 568d areinstalled on a card holder 568, and they are connected with grooved cams569a, 569b, 569c and 569d (The pin 568c is not shown in FIGS. 92 to FIG.94). One edge of an extension spring 570 is fixed to the side of thecarriage base 189, and the other edge of the extension spring 570 isfixed to the side of the card holder 568. The extension spring 570generates a downward pressure of the pins 568a to 568d moving downwardwithin the grooved cams 569a to 569d. A card bias spring 571 is fixed tothe end of the card holder 568 and generates a pressure in the directionof Y. Stoppers 572 and 573 are fixed to the apparatus base 21 (notshown). When the card holder 568, which has a role of pad, moves in thedirection of Y, the card holder 568 touches the stoppers 572 and 573,and then the movement toward Y is obstructed. The pressure pad 207 isfixed to the card holder 568. As shown in FIG. 94, the access opening189a is on the carriage base 189. The access opening 189a is provided sothat the carriage base 189 does not interfere with the turntable 15 whenthe carriage base 189 moves in the direction of X-Y.

Now operation of the card holding mechanism of the card reader of thisembodiment will be described.

FIG. 93A shows a sectional view at the line A--A of FIG. 92 and shows acondition that the magnetic card 1a can be inserted and extracted. Whenthe magnetic card 1a is inserted to a feeding path between the drivingroller 184 and the guide roller 185, a card sensor A (not shown) detectsthe magnetic card 1a. Then, the driving roller 184 starts rotating andthe magnetic card 1a is sent to a feeding path between the carriage base189 and the pressure pad 207. Then, the card bias spring 571 contactsthe magnetic card 1a, and the magnetic card 1a is pressed in thedirection of Y. Since the feeding power generated by the driving roller184 is larger than this pressure, the magnetic card 1a is never pushedback beyond the driving roller 184 in the direction of Y. That is themagnetic card 1a is never pushed back to the front of the apparatus.When a card sensor B (not shown) detects that the magnetic card 1a hasbeen moved into the card holder 568 perfectly, the stepping motorrotates to move the carriage base 189 in the direction of X. Then, sincethe card holder 568 is moved in the direction of C, that is downward, bythe effects of the grooved cams 569a to 569d and the pins 568a to 568d,the card 1a is held between the pressure pad 207 and the carriage base189. When the card holder 568 comes down, the card holder 568 is notmoved in the direction X nor Y. When the pressure pad 207 has finishedcoming down and the magnetic card 1a is pushed sufficiently by thepressure pad, the magnetic card 1a and the card holder 568 move in thedirection of X with the carriage base 189. Accordingly, it is possibleto perform a random access to the magnetic card 1a without generating aslip on the carriage base 189.

A starting point sensor (not shown), which is used for detecting themagnetic card 1a or the carriage base 189, detects one end of a range ofthe random access. When the carriage base 189 with the magnetic card 1amoves in the direction of X as stated the above, and when the magnetichead 13a or 13b is positioned at a rear track 63f as described inEmbodiment 53, the starting point sensor detects the magnetic card 1a orthe carriage base 189. In this case, the magnetic card 1a or thecarriage base 189 is at the one end of the range of the random access.It is also acceptable to install an end point sensor (not shown) todetect the other end of the range of the random access. This end pointsensor detects the magnetic card 1a or the carriage base 189 when themagnetic head 13a or 13b is positioned at a front track 63e.

It is also acceptable that the starting point sensor detects themagnetic card 1a or the carriage base 189 when the magnetic head 13a or13b is positioned at the front track 63e, and that the end point sensordetects the magnetic card 1a or the carriage base 189 when the magnetichead 13a or 13b is positioned at the rear track 63f.

A reflection type photoelectric switch or a light shield typephotoelectric switch can be used for the starting point and end pointsensors.

In the case of extracting the magnetic card 1a, the carriage base 189 ismoved in the direction of Y by motion of the stepping motor 221 and thelead screw 222. At this time, the card holder 568 moves simultaneously.When the front edge of the card holder 568 contacts the stoppers 572 and573, the movement of the card holder 568 in the direction of Y isobstructed. However, when the carriage base 189 continues to movefurther, the card holder 568 moves up to the location shown in FIG. 93Aby motion of the grooved cams 569a to 569d and the pins 568a to 568d ofthe card holder 568. Then, since the pressure of the pressure pad 207 onthe magnetic card 1a is removed, the magnetic card 1a is pushed backbetween the driving roller 184 and the guide roller 185 by the pressuretoward Y of the card bias spring 571. The magnetic card 1a is extractedout of the apparatus when the driving roller 184 starts rotating.

In FIGS. 95A and 95B, card lifters 574a to 574d made of elasticmaterial, such as plastic, are installed at the four edges of thecarriage base 189 described in Embodiment 65.

These card lifters 574a to 574d lift the magnetic card 1a above thecarriage base 189 to prevent interference with the turntable 15 when themagnetic card 1a moves into the carriage base 189. The card lifters 574ato 574d are fixed to the carriage base 189 and project upward from thebase surface of the carriage base 189. When the magnetic card 1a ispushed down to the carriage base 189 by the pressure pad 207, the cardlifters are not projecting upward as shown in FIG. 95C. To install thecard lifters 574a to 574d on the upper side of the carriage base 189, itis necessary to make the carriage base 189 hollow as shown in FIG. 95D.

Embodiment 67

FIG. 96 shows a situation where two positioning pins 575a and 575b arefixed to the carriage base 189 described in Embodiment 65.

The magnetic card 1a used in this case has positioning holes 576a and576b for positioning as shown in FIG. 97A. One of the two positioningholes 576a and 576b can be a circle or an oval.

If positioning holes 576c and 576d are made symmetric with respect to acenter point of the card against the positioning holes 576a and 576b asshown in FIG. 97B, the magnetic card 1a can be inserted oppositely intothe apparatus with respect to front and rear.

The operation of putting the magnetic card 1a on the carriage base 189will now be explained. When the magnetic card 1a has been fed into thecarriage base 189 perfectly and the carriage base 189 starts moving inthe direction of X, the positioning pins 575a and 575b should be forwardof the location of the positioning holes 576a and 576b as shown in FIG.98A. The card holder 568 and the magnetic card 1a do not move in thedirection of X initially as the carriage base 189 moves toward X. Whenthe positioning pins 575a and 575b move just under the positioning holes576a and 576b, the pressure pad 207 starts pushing the magnetic card 1afrom above as shown in FIG. 98B. Then, the front edge of the card biasspring 571 contacts the carriage base 189. The pressure toward Y on themagnetic card 1a by the card bias spring 571 is removed. Therefore, themagnetic card 1a slides down the outside of the driving roller 184 andis pulled toward X. There are holes 582a and 582b on the pressure pad207 to prevent interference with the positioning pins 575a and 575b. Inthe situation of FIG. 98B, the pressure pad 207 moves downward to pushthe magnetic card 1a toward Y with respect to the magnetic card 1a.Therefore the location of the holes 582a and 582b deviates toward X fromthe location of the positioning pins 575a and 575b as shown in FIG. 98B.

Embodiment 68

FIG. 99 shows that the card lifters 574a to 574d are installed on thecarriage base 189 described in Embodiment 67.

Since the magnetic card 1a is lifted by the card lifters 574a to 574d,the magnetic card 1a does not contact the positioning pins 575a and 575bor contacts then only a little to obtain very small shock when themagnetic card 1a moves the carriage base 189. The magnetic card 1a canbe lifted up from the positioning pins 575a and 575b by the card lifters574a to 574d in extracting the magnetic card 1a.

Embodiment 69

In FIG. 100A, the positioning pins 575a and 575b described in Embodiment67 are supported elastically by flat springs 577a and 577b fixed to theback side of the carriage base 189.

Since the positioning pins 575a and 575b move downward even when themagnetic card 1a contacts the positioning pins 575a and 575b, themagnetic card 1a is damaged only a little in being inserted andextracted. It is also acceptable to install the card lifters 574a to574d described in Embodiment 68.

The shapes of the positioning pins 575a and 575b can have a taper asshown in FIG. 100B. In Embodiment 67, it is described that one of thepositioning holes 576a and 576b can be oval. Diameter D at the foot ofthe positioning pin corresponding to the circular positioning hole islarger than diameter of the circular positioning hole. Diameter D at thefoot of the positioning pin corresponding to the oval positioning holeis larger than minor axis of the oval positioning hole. By defining thesize of the positioning holes as the above, the positioning pins 575aand 575b can be tightly placed into the positioning holes 576a and 576b,which has an effect of improving the positioning accuracy of themagnetic card 1a.

After the positioning pins 575a and 575b have been placed into thepositioning holes 576a and 576b, the magnetic card 1a is pushed onto thecarriage base 189 by the pressure pad 207. When the magnetic card 1a ispushed onto the carriage base 189, the flat springs 577a and 577b benddownward as shown in FIG. 100B and then an upward spring power isgenerated. As the flat springs 577a and 577b are cantilever springs, thepositioning pins 575a and 575b are inclined and the positions of thepositioning pins 575a and 575b are deviated with respect to a horizontaldirection when the flat springs 577a and 577b bend. Therefore, in orderto improve the positioning accuracy of the magnetic card 1a, it is alsoacceptable to make the structure of the positioning pins 575a and 575bmove upward and downward vertically. Namely, a guide part 575c should beinstalled on the carriage base 189 as shown in FIG. 100C and thepositioning pins 575a and 575b, pressured upward by a compression spring575d, should be put into the guide part 575c.

Although the flat springs 577a and 577b and the compression spring 575dare used for pressuring the positioning pins 575a and 575b in thisembodiment, a gimbal spring or magnetic power can be used instead of theflat springs and the compression spring.

Embodiment 70

The positioning holes 576a and 576b of the magnetic card 1a were on thesame line which is parallel to the inserting direction in Embodiments 67to 69. The positioning pins 575a and 575b correspond to the positioningholes 576a and 576b. When the magnetic card 1a contacts the positioningpins 575a and 575b in moving into the carriage base 189, the forwardpositioning hole 576b contacts the positioning pin twice. Therefore, thepositioning hole 576b is damaged around the hole, and then positioningaccuracy will be deteriorated. As the positioning pin 575a is moved tothe forward positioning hole 576b, a problem may occur in the insertingoperation.

The positioning holes in this embodiment are not aligned on the sameline which is parallel to the inserting direction. Two positioning holes576e and 576f are made sideward at the front of the magnetic card 1a asshown in FIG. 101. The positioning pins 575e and 575f of the carriagebase 189 are also aligned sideward corresponding to the positioningholes 576e and 576f as shown in FIG. 102. It is also acceptable to maketwo holes 576g and 576h not on the same line, namely deviated a littlefrom one another, as shown in FIG. 103 and to install positioning pinscorresponding to the two holes.

Embodiment 71

The positioning pins 575a and 575b project from the base surface of thecarriage base 189 in Embodiment 69. The front edges of the flat springs577a and 577b are bent in this embodiment as shown in FIG. 104A. As thecarriage base 189 moves in the direction of Y, the front edges of theflat springs 577a and 577b are pushed down by arms 578a and 578b fixedto the apparatus base 21 as shown in FIG. 104B. By this method, themagnetic card 1a can avoid interfering with the positioning pins 575aand 575b when the magnetic card 1a is inserted. Accordingly, the space Hof the feeding path between the carriage base 189 and the pressure pad207 can be reduced, which has an effect of downsizing the apparatus.

In this embodiment, it is also acceptable to have a taper as the shapeof the positioning pins 575a and 575b as mentioned in Embodiment 69.

Embodiment 72

In the above embodiments 65 to 69, the grooved cams 569a to 569d on thecarriage base 189 are used for lifting and lowering the card holder 568.While the carriage base 189 moves in the direction X or Y, the cardholder moves up or down. Namely, the card holder 568 moves diagonallywith respect to the carriage base 189.

In this embodiment, the card holder moves up and down vertically withrespect to the carriage base. FIG. 105 shows the carriage base 189 andthe card holder 568 of this embodiment. There are square holes 579a to579d on the carriage base 189. Foot parts 580a to 580d of the cardholder 568 are inserted into the square holes 579a to 579d. In thiscase, each of the foot parts is inserted into the square hole and canmove in the vertical direction C or D (Foot parts 580c and 580d are notshown). One side of each the foot parts 580a to 580d is slanting. Oneedge of the extension spring 570 is fixed to the carriage base 189, andthe other edge is fixed to the card holder 568. Both edges are pressedclose to each other. The pressure pad 207 is the same pad as that ofembodiment 1.

In FIG. 106A, blocks 581a to 581d (blocks 581c and 581d are not shown)are fixed to the apparatus base 21, and they face the foot parts 580a to580d. When the carriage base 189 and the card holder 568 move in thedirection Y, the foot parts 580a to 580d contact the blocks 581a to581d. Then, the card holder 568 is lifted in the direction D because theslanting sides of the blocks and foot parts function as a cam. Itbecomes possible to insert and extract the magnetic card 1a. It isnecessary to move the carriage base 189 in the direction X in order tolower the card holder 568. By doing this, the magnetic card 1a is heldbetween the pressure pad 207 and the carriage base 189.

It is also acceptable to use the card lifters 574a to 574d and thepositioning pins 575a to 575d, described in the above embodiments, forthe structure of this embodiment. Using flat springs 577a and 577b forthe positioning pins 575a and 575b, and using arms 578a and 578b forlifting and lowering the flat springs 577a and 577b are also acceptable.

The operation of positioning the magnetic card 1a having the positioningholes 576a and 576b, on the carriage base 189 will now be described.When feeding the magnetic card 1a into the carriage base 189 is completeand the carriage base 189 starts moving toward X, the positioning pins575a and 575b should be just under the location of the positioning holes576a and 576b as shown in FIG. 107. Then, the carriage base 189 startsmoving in the direction X, and the pressure pad 207 moves downvertically to push the magnetic card 1a.

If pressure of the card bias spring 571 against the magnetic card 1a isremoved, the front edge of the magnetic card 1a moves away from thedriving roller 184. It becomes possible for the magnetic card 1a tobeing together the positioning pins 575a and 575b smoothly. Thefollowing structure is also acceptable. FIG. 108 shows an enlargement ofthe carriage base 189 and the card holder 568 in this case. Especially,the enlargement of the edge with respect to the direction X is shown.The card bias spring 571 is fixed to the edge of the card holder 568.The card bias spring 571 includes a card bias part 571a at the center ofthe card bias spring 571 and tongues 571b and 571c (the tongue 571c isnot shown) at both edges of the card bias spring 571. A notch 584 ismade at the location corresponding to the card bias spring 571, on thecarriage base 189. The notch 584 includes a side 584a corresponding tothe card bias part 571a, and sides 584b and 584c corresponding to thetongues 571b and 571c. When the magnetic card 1a is not located betweenthe carriage base 189 and the card holder 568, the card bias part 571acontacts the side 584a. If the magnetic card 1a is inserted between thecarriage base 189 and the card holder 568, the magnetic card 1a contactsthe card bias part 571a and applies pressure toward Y as shown in FIG.109B. When the card holder 568 moves down to the carriage base 189, thetongues 571b and 571c contact the sides 584b and 584c as shown in FIG.109C. Then, the card bias spring 571 rotates in the direction of Z, sohorizontal pressure on the magnetic card 1a is removed. In order of FIG.109C to FIG. 109B, the magnetic card 1a is pushed in the direction ofthe driving roller 184, and the magnetic card 1a is extracted along therotation of the driving roller 184.

Embodiment 73

In Embodiment 72, cams are used for lifting and lowering the card holder586 with respect to the carriage base 189. A method of using a link willbe described in this embodiment.

FIGS. 110A and 110B show sections of the device of this embodiment. Thecarriage base 189 and the card holder 568 are pressed in the directionof their mutual approach, by the extension spring 570. Bases 585a and585b are fixed to the apparatus base 21. Links 586a and 586b are fixedto the bases 585a and 585b and can rotate in the direction E or F. Thelinks 586a and 586b are pressed to rotate in the direction E by theextension springs 587a and 587b. When the carriage base 189 moves towardY and contacts the edge of the links 586a and 586b, the links 586a and586b rotate in the direction F. Then, the other edges of the links 586aand 586b lift the foot parts 580a and 580b as shown in FIG. 110B, and itbecomes possible to insert or extract the magnetic card 1a.

In the above embodiments 65 to 73, the pressure pad 207 is used as thepad. The support pad 539 described in Embodiment 40 or one side of thecard holder 568 can be also used as the pad.

Embodiment 74

In embodiments 65 to 73, the turntable 15 does not move and the magneticcard 1a moves with the movement of the carriage base 189 when randomaccess is performed. In this embodiment, the turntable 15 moves alongthe long side of the magnetic card 1a when random access is performed.

This embodiment will now be explained with reference to FIGS. 111 to113. In FIG. 112, a carrier 588 applied with the turntable 15 isconnected to the guide rod 220. A needle 589 and a pressure spring 590are fixed to the carrier 588. This needle 589 is connected with the leadscrew 222. The pressure spring 590 presses the connection between thelead screw 222 and the needle 589 from the opposite side.

The carriage base 189 is fixed to the apparatus base 21 by a fixing part(not shown). The width P of the inside measurement of the card holder568 is longer than the width Q of the outside measurement of thecarriage base 189. As shown in FIG. 111, there is a hole 591 on the sideof the carriage base 189. Holders 592 and 593 are fixed to the apparatusbase 21. There is an oval hole 594 on the holder 593.

One end of an arm 595 is fixed to the holder 592, and this end canrotate. The other end of the arm 595 engages the hole 591. One end of anarm 596 can be put in the hole 594 of the holder 593. The other end ofthe arm 596 is fixed to the card holder 568, and this end can rotate.The arms 595 and 596 are connected to one another rotatably at eachcenter, and they form a parallel link. As shown in FIG. 113, one end ofa wire 597 is fixed to the carrier 588, and the other end of the wire597 is fixed to the arm 596.

When the carrier 588 moves in the direction X and the magnetic head 13aor 13b moves toward X farther than the rear track 63f of the magneticcard 1a described in Embodiment 53, the wire 597 strains and draws thewire fixed to the end of the arm 596 in the direction X. Then, the cardholder 568 moves up and the conditions of feeding the magnetic card 1ain and out are established. When the carrier 588 moves toward Y afterthe magnetic card 1a is inserted, the wire 597 becomes loose and thecard holder 568 moves down, and then the condition of reading/writing isestablished.

In the case where the driving roller 184 is used for feeding themagnetic card 1a in and out as shown in FIG. 92 for this embodiment inwhich the magnetic card 1a does not move in the direction X, it isacceptable that the driving roller 184 is moved downward by an avoidingmechanism (not shown) to avoid interference with the magnetic card 1awhen the magnetic card 1a is pushed onto the carriage base 189.

One end of a range of the random access can be detected by the startingpoint sensor (not shown) which detects the carrier 588. When the carrier588 moves toward X and the magnetic head 13a or 13b is positioned at therear track 63f as described in Embodiment 53, the carrier 588 isdetected by this starting point sensor. In this case, the carrier 588 isat one end of the range of random access.

It is acceptable to install the end point sensor (not shown) to detectthe other end of the range of random access. The end point sensordetects the carrier 588 when the magnetic head 13a or 13b is positionedat the front track 63e. It is also acceptable that the starting pointsensor detects the carrier 588 when the magnetic head 13a or 13b ispositioned at the front track 63e, and the end point sensor detects thecarrier 588 when the magnetic head 13a or 13b is positioned at the reartrack 63f. A light shield type or a reflection type photoelectric switchcan be used as the starting point and end point sensors.

In the apparatus in which the magnetic card 1a moves, it is necessary tomaintain a specific space to move the carriage for random access in theapparatus. The specific space is the same length as the total of thelength of the magnetic card 1a and the length of movement of themagnetic card 1a. On the other hand, in the apparatus in which theturntable 15 moves as this embodiment, it is necessary to maintain thespace the same as the length of the magnetic card 1a, which produces aneffect of making the length of the apparatus short.

The card reader of the present invention has the above structures. Sincethe magnetic card is held between the carriage base and the card holder,positioning accuracy is improved. As the positioning pins are used forpositioning the card, positioning accuracy is also improved.

In general, the apparatus, such as the apparatus above stated, isexpected to be small size and to memorize large amounts of data.Accordingly, it is necessary to clarify the relation between theelements of the apparatus and the data amount. The relation between theangle α and the total track length M obtained by adding each tracklength have been computed in expressions (10) to (15). The range of theangle α has been defined in expression (24). These expressions are inthe case where two tracks necessarily correspond to a head rotationcenter. There is a possibility that one track corresponds to the headrotation center depending upon a shape of the card and so on. Though nopractical large problem is caused, the above computations are performedapproximately. The expression (10) "X=P·cosα" is not correct strictly,for example. Although the number of the tracks N should be an integer, Nin the expression (13) is not necessarily an integer. A more generalcomputation method for the angle α and the track pitch P which maximizethe total track length M will now be described as follows. Todistinguish the following expressions from the above expressions,variables different from the variables used in the above expressions areused, even when both variables mean the same.

The following are defined as known variables in advance for thecalculation (refer to FIG. 114).

    ______________________________________                                        Length of recording region  Lr                                                Radius of track             Rt                                                Tolerable minimum space between neighboring tracks                                                        Tpmin                                             ______________________________________                                    

Lr and Rt are defined by the size of the magnetic card 1a, partsallocation in the apparatus and so on. Tpmin is defined by the width ofthe track and the characteristics of the magnetic head. The locus of thehead rotation should be within Lr.

The following are calculated from the above known variables with a trackpitch Tp.

    ______________________________________                                        Recording angle          θ                                              Length of one track      Lt1                                                  Number of tracks         Nt                                                   Total length of tracks   Lt                                                   ______________________________________                                    

It is necessary to repeat the calculations with changing Tp to determinea track pattern. The track pattern is determined based on the Tp whichmakes Lt maximum and θ corresponding to the Tp.

The procedure of the computation will be explained as follows.

Procedure 1. Assume temporary pitch Tp

Procedure 2. Based on the Tp, calculate the recording angle θ (degree)which makes the space between two neighboring tracks be Tpmin.

Now, the calculation will be explained in reference to FIG. 115. Acircle whose center is the origin is defined as circle C1. A circlewhose center is (Tp, O) is defined as circle C2. An intersection betweena line which passes the center of the origin and has an angle θ, and thecircle C1 is defined as a point A (xa, ya). Another intersection betweenthe line which passes the center of the origin and has an angle θ, andthe circle C2 is defined as a point B (xb, yb). xa is the x-coordinateof A, and ya is the y-coordinate of the point A. xb is the x-coordinateof B, and yb is the y-coordinate of the point B. Assuming that distanceAB between the points A and B is defined as distance between the circlesC1 and C2 at the point A, the following calculation can be made.

    AB=(xb-xa)/cos θ

This expression can be expressed as follows.

    AB=Tp×cos θ+√(Rt.sup.2 -Tp.sup.2 ×sin.sup.2 n θ)-Rt

The angle θ which makes this AB be the same as Tpmin is the recordingangle. To calculate this recording angle θ, the following function F (θ)is defined.

    F(θ)=Tp×cos θ+√(Rt.sup.2 -Tp.sup.2 ×sin.sup.2 θ)-Rt-Tpmin

By solving F (θ)=0 with respect to θ, the recording angle can beobtained. The Newton method using an approximate solution to solve asubject is used. Procedure 3. Calculate Lt1 which is the length of onetrack.

    Lt1=π×Rt×θ/90

θ has been already calculated in the procedure 2.

Procedure 4. Calculate Ls which is length of the range of tracks beingwritten. This calculation method will now be explained with reference toFIGS. 116 to 118. Ls is a sum of "a" and "b" shown in FIG. 117 or 118.In FIGS. 117 and 118, a solid line indicates a track and a dotted lineindicates a locus of the head. Arcs 598 and 599, each of whose centralangles is 2θ, are written facing oppositely. In this case, the length ofthe central blank part is defined as L0 and distance between the twoedges of the extended locus of the arcs is defined as L1.

    L0=2×Rt×(1-cos θ)

    L1=4×Rt-L0=2×Rt×(1+cos θ)

(1) Case of Lr>L1

The right and left most inner tracks 600 and 601 can approach until theycontact each other as shown in FIG. 117. Even when the tracks 600 and601 contact, the head locus does not move out of the recording region.##EQU4## (2) Case of Lr=<L1

The right and left most inner tracks 602 and 603 can not approach soclose that they contact each other as shown in FIG. 118. When the tracks600 and 601 approach to close that they contact, the head locus movesout of the recording region. ##EQU5## Procedure 5. Calculate the numberof tracks Nt Assuming that the tracks are arranged symmetrically withrespect to right and left, Nt is an even number.

    Nt=INT(L /2/Tp+1)×2

INT is an integer value of th expression in the above parentheses.

Procedure 6. Calculate length of total tracks Lt.

    Lt=Lt1×Nt

The above procedures are repeated with changing Tp to determine thepitch Tp which makes Lt maximum and the recording angle θ correspondingto this pitch Tp. Then, an outline of the track pattern will bedetermined:

When Lr>L1 as stated in the procedure 4, only one track can be providedfor a head rotation center at the part out of the recording region L1.For example, track 605 can not have a facing track having a samerotation center 604 as shown in FIG. 117. It happens that the facingtrack for the track 605 crosses other tracks if the facing track iswritten symmetrically against the rotation center 604. On the otherhand, in the case of L1>=Lr as stated in FIG. 118 or in the regioninvolved in L1 shown in FIG. 117, two facing tracks placed symmetricallycan be provided for one rotation center. Tracks 600 and 607 for therotation center 606 in FIG. 117 and tracks 602 and 609 for the rotationcenter 608 in FIG. 118 are examples of the above.

In the case of Lr>L1, normal writing/reading operation can not beperformed practically when the right and left most inner tracks 600, 601contact one another as shown in FIG. 117. Namely, it is necessary tomaintain space between the innermost tracks, for example by deleting thetwo right and left innermost tracks 600, 601.

FIG. 119 shows an example of the above calculation results. The relationbetween Tp and Lt is described regarding Rt as a parameter. In thiscase, Lr=80 (mm), Tpmin=0.12 (mm). When Rt=25 (mm), Tp becomes 0.18 (mm)and the total track length Lt becomes about 14,000 (mm) which is themaximum. The recording angle θ is about 48 degrees at this time. When Tpis between 0.16 (mm) and 0.21 (mm), the total track length becomes morethan about 13,300 (mm) which is 95% of the maximum. In this range, therecording angle θ is about 41 degrees to 54 degrees.

What is claimed is:
 1. A card for recording a data, comprising arecording area having a plurality of recording tracks for recordingdata, wherein the plurality of recording tracks includes a plurality ofsets of two arc tracks, each set being located at a place on onecircumference of the card, and wherein radii of circumferences at thesets are substantially identical and centers of circumferences of thesets are aligned along a common linear axis and separated from onecenter point to the next center point by a predetermined pitch andwherein each set is arranged to be selectively accessed during arotation of an access head about said one circumference and while saidaccess head is centered at a single center point that is stationaryalong said common linear axis during said rotation about said onecircumference, wherein the arc tracks have a track pitch P=X/cos αwherein x is a track width and α is a half of a center angle of the arctracks.
 2. The card of claim 1, wherein the angle α is between 40degrees and 55 degrees.
 3. The card of claim 1, wherein:one set of twoarc tracks is a first track set located at a first location on the card;and another set of two arc tracks is a second track set located at asecond location on the card; wherein the first location and the secondlocation are on a same side of the card; said first track set containsan address area designating said first track set as a first track; andsaid second track set contains an address area designating said secondtrack set as a second track.